'98 V70 GLT Transmission problems...

[bmdubya1198]

Again, I have to tell you, thank you so much for helping me with this! The information you've been providing has been extremely helpful!
I have replaced both the TCM and the ECM, however currently, the original units are in the car, because I have discovered that they are both good.
The Volvospeed thread is here: http://volvospeed.com/vs_forum/topic/17 ... rd-98-v70/

[esl_97_850_T5]

bmdubya1198,

Short summary of how to eradicate the P1618 and EFI-335 problem:
- Verify proper grounds Motronic 4.4 (M44) pins A13, A28, A42.
- Verify car's Ground Points 31/71 (I997 & presumably 1998), 31/32 and 31/33 (1996 & possibly 1998).
- Isolate short circuit to supply voltage (or alternatively an open circuit) between AW 50-42's TCM (aka 4/28 on wiring diagrams, aka ECU 6E)'s pin B15 to M44 (aka "the ECM", aka 4/46 on wiring diagrams, aka EU 7A)'s pin B26.
- Correct any of the 3 above items which are the problem.
- If not solved, isolate other grounding, short circuit (either to supply or to ground), or open circuit problems, then correct. [This is the appropriate stage for disconnecting the ABS completely to see if it is contributing to the problem. This is also the appropriate stage (if you haven't done it already) to check all your 11/xx grounds.]
- If not solved, replace damaged wiring bundles.
- Get the OTP 850 Repair DVD so you can do research yourself to shed greater light on the situation.
- Continue to consult 98 V70 gurus on any of the many Volvo forums.

The guts of this post is item 5 -- ie, my suggested detailed steps to diagnose the P1618 and EFI-335 combo -- derived, as best I understood them, from the OTP 850 Repair DVD, and mashed up with info from other places -- prefixed with some concise notes of what documents were used from the DVD. You can immediately jump to step 5 if you want to save some time. But I suggest to at least quickly skim everything first.

1. MVS's volvo-diagnostic-codes-1995-to-1998 says A2 335 (which we know as EFI-335) is due to P1617 and P1618.

2. The page in item 1 also references the https://www.matthewsvolvosite.com/forums ... =1&t=27973 thread. That thread is for a '99 S70 T5, but the two things I noticed in that thread that seem possibly pertinent to your '98 V70 case are:

2a. jblackburn said "The other thing people suggest is a bad transmission ground wire."

When you were checking grounds before, did you check the transmission ground?
For that matter, where is the transmission ground? I didn't check on that.

2b. A bad ABS is correlated somewhat with P1618. That surprised me. It's worth noting that more than 1 experienced Volvo guru has encountered a bad ABS causing P1618, including none other than the venerable Matty Moo. Though Matty Moo says (consistent with the link mentioned in item 1) that P1618 is sometimes from the TCM. I don't know if that ABS - P1618 correlation was something new for '99 S70. And I don't know if that is significant for your situation or not.

There is one person at MVS that documented several months ago that his bad ABS module disrupted *all* communication via the OBDII port. He had to remove his bad ABS module in order to communicate with the COMBI, etc.

To tell you the truth, I don't think this is your problem, but maybe at some time in the future, if all else fails, you might want to totally disconnect the ABS module's connector and its 2-pin power connector, then try to talk to the AW 50-42 and try to clear the COMBI DTCs. I don't recall you having done that yet. The only reason I mention this now is "a bad ABS problem" was part of the thread (in item 2) that caused me to mention "bad transmission ground" as a possible cause of EFI-335 / P1618.

3. IMPORTANT -- Let's delve into this grounding stuff in more detail, since the OTP 850 DVD's initial diagnostic steps -- ***BEFORE*** beginning testing of the M44's signal pins -- is to verify that the grounds are working. I purposely left that out of the previous post showing the two sources of M44 connector A and connector B pins, since I knew this grounding issue was going to be treated thoroughly in this post.

3a. First, let's review your history. Has your checking of ground points been complete?

3a1. Previously, did you check ground point 31/71 (which for a '97 850 is in front of the washer refill and is probably beneath the right passenger headlight)? This is likely where at least 3 of your M44 ECM grounds and 2 of your AW 50-42 TCM grounds are connected. 31/71 is a VERY IMPORTANT grounding point to check in your EFI-335 case.

- See location of "Ground point 31/71" in 1997_850_Wiring_Diagram.pdf that can be downloaded using "1997 Volvo 850 Wiring Diagrams" link in my previous post.

- See the "July 17, 2011 - MARTYN P ROWSON" comment in this https://www.matthewsvolvosite.com/forums ... 42#p297053 post by a wise, 18 years experienced Volvo sage that basically says:

>>>>>>>> 90% of the 850 / S70 / V70 / C70 problems with the 5-cylinder engines that cause the CEL to turn on are due to a dirty or loose ground under the right headlight. <<<<<<<<<<

After reviewing the 1996 vs. 1997 wiring diagrams and seeing that ECM and TCM grounds go to 31/71 in 1997, whereas they go to 31/32 and 31/33 in 1996, we might take some liberty and adapt that further to say:

*** Many of the '97-'98 850 / S70 / V70 / C70 / XC70 problems that cause the CHECK ENGINE light to come on are due to a dirty or loose Ground Point 31/71 near or under the right headlight!!!!!! ***

I wouldn't be surprised if many '96 850 problems that cause the CHECK ENGINE light to come on could be explained similarly, except for them the source of the problem would be dirty or loose Ground Points 31/32 and 31/33 (instead of a non-existent 31/71).

- jblackburn guessed correct. It is the major ground point for the M44 (at least starting for model 1997), since according to the OTP Volvo 850 DVD, the very first thing that is checked before debugging the EFI-335 / P1618 error is to check that each of the M44 pins A13, A28, A42 back to battery negative have 0 ohms resistance, and the OTP's 1997 wiring diagram for M44 show those pins going to 31/71. Further research on the DVD reveals it is indeed the major ground point for the "entire ECU box", both ECM and TCM.

See item 5 below for the detailed suggested test sequence.

3a2. Previously, did you check ground terminals 31/32 and 31/33 on the engine rear and their cables for an open circuit? Also, did you check ground lead between engine and chassis for an open circuit?

In addition to 31/71, 31/32 and 31/33 are supposedly VERY IMPORTANT grounding points to check for a 97 850 EFI-335 case (according to the OTP 850 DVD's 1997 M44 documents). However, after further comparison of the 1996 vs. 1997 wiring diagrams, I've come to the conclusion for 1996, 31/71 is non-existent and what's important to check for EFI-335 on 1996 850 is grounds 31/32 and 31/33. For 1997, 31/71 is what's important to check for EFI-335 on 1997 850. I see no evidence from the 1997 M44 wiring diagrams that 31/32 and 31/33 are user by M44 or TCM. I assume they didn't get the docs properly updated or they purposefully chose to leave the diagnostics broadbased so it would handle both the 1997 as well as 1996 cases. I'm just assuming that a '98 V70 is similar to a '97 850. If that's true, then 31/71 is where the '98 V70 grounds for M44 and TCM go. bmdubya1198, it might be wise of you to go ahead and check all 3 ground points 31/71, 31/32, and 31/33, just like OTP 850 DVD suggests, just to be sure. But don't be surprised if 31/32 and 31/33 are not used by M44 and TCM as grounding terminals.

3a3. Have you verified that all the following ground points are working as intended (where this list is taken from OTP 850 DVD TP-3917201 "List of components" about 1 or 2 pages from the end, this list is missing from the MVS download of 1997_850_Wiring_Diagram.pdf, this list is available in a 1992-1996 850 Haynes manual (except that 31/71 is missing in Haynes manual and a 31/65 "Ground point, steering column" is included in Haynes manual)):

- 31/4 -- Ground point, engine (ground point, battery - engine)
- 31/7 -- Ground point, A pillar driver side
- 31/11 -- Ground point, trunk, left side
- 31/12 -- Ground point, trunk, right side
- 31/15 -- Ground point, A-pillar passenger side (ground point for OBDII socket and many other things)
- 31/32 -- Ground point, on engine (power ground) / ground point at engine (ground point #2 for ECM and TCM)
- 31/33 -- Ground point, on engine (signal ground) (ground point #3 for ECM and TCM)
- 31/44 -- Ground point, engine compartment (ground point, battery - body)
- 31/47 -- Ground point, left cross member
- 31/48 -- Ground point, right cross member
- 31/50 -- Ground point, central electrical unit, power ground (ground point for COMBI and many other things)
- 31/51 -- Ground point, central electrical unit, signal ground
- 31/52 -- Ground point, DI power stage and ignition coil
- 31/55 -- Ground point, engine cooling fan
- 31/71 -- Ground point, right side member in engine compartment (ground point #1 for ECM and TCM)

I added a little bit more description relating to OBDII port, COMBI, ECM, and TCM, since those are the things that relate to all your present 98 V70 errors.

***IMPORTANT*** >>>> In particular, I want to draw your attention to 31/71. A picture of the location of the 31/71 ground point is in the 1997 850 Wiring Diagrams .pdf linked to from my most recent, previous post. It's under the passenger headlight.

3a4. In my car I can not see how to easily get to ground point 31/71, so I'll write the instruction to test directlly to the battery negative terminal for anything which needs to test if 31/71 is functional as a reliable ground point. And on that point, plagiarizing and paraphrasing some words from https://www.matthewsvolvosite.com/forums ... 56#p263856 and adapting to your specific situation, we conclude...

You should have the same voltage from positive at the battery to your 1998 V70 31/71 ground terminal -- same as across the two terminals at the battery.

Check the resistance from the battery's negative post to the 31/71 ground point. It should be 0 ohm. If it isn't, or if you can change it by wiggling things, then you have a bad connection somewhere. Try pushing up and down on the right side of the car. Try wiggling wires around 31/71 or leading from 31/71 back to the ECM.

"Test leads with alligator clips make" testing continuity all the way back to the battery negative terminal "a pretty easy exercise. In a pinch use a jumper cable from the negative terminal only if you don't have long enough leads...just make sure the jumper cable you use has zero resistance, or at least measure it and know what it is."

3a5. I have located a picture that shows all the ground points. It's all the way back for a 1996 850. It is in the "Ground Points" section of the OTP 850 DVD documents "TP-3911202" and "TP-3911032". The first one appears to be available as a MVS download: 1996_850_wiring_diagram.pdf. I didn't check this downloadable version to compare it to the OTP version. The OTP version is missing the ground point 31/71, but you already know that 31/71 is visible on the 1997 850 Wiring Diagram. My belief is these 1996 group point locations are probably applicable to your '98 V70. Someone more knowledgable than I can verify that is true or not.

4. The OTP Volvo 850 DVD, in a couple of different "Engine management system Motronic 4.4 850..." documents, says P1617 and P1618 can both cause EFI-335, but those documents provide a lot more information about what both of them mean vs. the the MVS table of DTC codes linked to in item 1 above.

4a. The OTP Volvo 850 DVD M44 documents that I looked at (TP-2318201 and TP-2318031) both said P1617 and P1618 are a "Cable fault between AW 50-42 transmission control module (TCM) and Motronic 4.4 engine control module (ECM)" and that it illuminates the CEL / MIL light.

4b. However, P1618 is for a "High" condition (not for P1617's "Low/Missing/Fault" condition).

5. MOST IMPORTANT: Detailed test sequence. This item's wording is not pretty. But I'm too tired to make it more palatable. This item 5 is the guts of this post.

First, some preface and history:

Code: Select all

From OTP Volvo 850 DVD using a combination of:
- TP-2318031 & TP-2318201 (ie, 1997 M44): 
  * "DTC Table", p43; "OBD-II Codes, Table", p269;
  * "Signal Description Motronic 4.4", pp228-230.
    [https://www.matthewsvolvosite.com/forums/viewtopic.php?p=385136#p385136 post
    describes how combining Dilemma's "Volvo Motronic 4.4.pdf" "ECU Pinout" table
    and volvopedia.de's http://www.volvopedia.de/index.php?title=Motronic_4.4
    comes close to equaling pp228-230, except that combination does not include
    the missing instructions, and except that combination includes the extra
    wire Color column that Dilemma included.]
- TP-2308032 (ie, 1996 M44): 
  * "DTC Table", p77; 
  * "BB. EFI-335 Cable fault between AW 50-42 transmission control module (TCM) and Motronic 4.4 engine control module (ECM)", pp275-280;
  * "OBD-II Codes, Table", p670;
- TP-3917201 [a higher quality version of MVS's 1997_850_Wiring_Diagram.pdf 
  download]: 
  * "List of components", at end of manual [a complete list!!!];
  * "Sequential Fuel Injection (SFI) System, Motronic 4.4 (B 5254 S)", pp20-21;
  * "Ground Point 31/71";
  * "Electrical Distribution", p10;
  * probably some of the other diagrams in TP-3917201;
where:
  * I tried to use the scanned page numbers, rather than the 
    Locklizard Safeguard secure viewer page numbers 
    (which are oftentimes 1-4 pages higher than the scanned page numbers).
    But I don't swear that I did that consistently, and 
    I didn't spend the time to double-check it;
the "BB. EFI-335 Cable fault ... pp275-280" is the section that has the 
primary diagnostic information, we glean from that section
(and a mish-mash of all the others mentioned):
    * On engine start, ECM checks for a "signal too high" condition:
      - open in signal cable, or
      - short to supply voltage in signal cable.
    * When engine is running, ECM checks for a "signal too low" condition:
      - short to ground in signal cable.
    "BB B. Other diagnostic trouble codes (DTCs) and status messages", p276.
    * Shows a picture of a VST and one of its status messages:
          PERMANENT FAULT
          SIGNAL TOO HIGH
          P1618
      That's probably what you would see if you hooked your car up to a VST 
      and communicated with the M44 in this present situation, where:
      - Torque and ElmBasic/kwpd3b0_interpreter saw P1618 
        (using OBDII emission diagnostics protocol) and 
      - Brick-Diag Free v0.0.6.6 and Vol-FCR saw EFI-335 from ECU 7A (ie, M44)
        (using KWPD3B0 protocol).
    * There are apparently 4 status messages that the VST might display for 
      EFI-335.  Their associated conditions are:
      - Signal too high.  Permanent fault.  See p277.
      - Signal too low.  Permanent fault.  See p278.
      - Signal too high.  Intermittent fault.  See p279.
      - Signal too low.  Intermittent fault.  See p280.
      Your case is either p277 or p279, since you are getting P1618 and 
      OTP 850 DVD's TP-2318031, TP-2318201, and TP-2308032 .pdc's all say 
      in their "DTC Table" section that P1618 is the "signal high" case 
      instead of the "signal low" variation of EFI-335.
      A reasonable guess (from everything you've said) is that your problem is
      permanent instead of intermittent.
      So let's assume p277 is the proper diagnostic page.

Then, the diagnostic sequence:

Code: Select all

    * Here's the actual diagnostic sequence for a permanent, signal too high, P1618 condition:
      - Turn off ignition.  [I'd take the key out of the ignition also.]
      - *** IMPORTANT ***
        *** Wait 2.5 min after ignition off so main relay has time to 
        *** interrupt its power supply.
      - After the main relay has interrupted its power supply...
      - Disconnect M44 ECM.
      - Turn off all equipment in car that consume battery power, 
        eg, interior lighting, radio, tools in OBDII port, etc.
      - Connect ohmmeter between battery negative and the special (high cost) 
        test box's terminal #13, #28, and #42
        (after having connected to M44's connector A)
        to see if each of them reads ~0 ohms for each reading.  
        This basically tests the following M44 pins
        are each grounded properly through ground point 31/71 
        (see 1997 850 wiring diagram, p20, about 1/3 the way down on 4/46):
        * A13 -- Power ground.
        * A28 -- Power ground for ECM.
        * A42 -- Signal ground for ECM (measured to battery negative terminal)
        [bmdubya1198, since your volvospeed friends have indicated all you
        need as a multimeter, just forget the "test box" and connect
        the ohmmeter directly from battery negative and each of the 3 pins.]
      - If any of the 3 reading is incorrect, ie, not ~0 ohms:
        * Check for damaged pins or sockets on the ECM or 
          control module cage connectors,
          especially those of A13, A28, and A42.
        * Fix any damaged pins or sockets before proceeding any further.
        * Repeat the ohmmeter test between the 3 pins and battery negative.
      - If any of the 3 reading is still incorrect, ie, not ~0 ohms:
        * Check ground terminals 31/32 and 31/33 at rear of engine and 
          their cables for an open-circuit (according to MMM A2).
        * Check contact resistance and oxidation (according to MMM A5).
        * Fix any problems with 31/32 and 31/33 before proceeding any further.
        * Repeat the ohmmeter test between the 3 pins and battery negative.
      - If any of the 3 reading is still incorrect, ie, not ~0 ohms:
        * Remove whatever is necessary so you can access the 31/71
          ground point.
        * Check ground terminal 31/71 in front of washer fluid container
          and behind or below the right headlight.  Check both the terminal
          itself.
        * Check the cables leading to it from the ECU box --
          especially the wires from M44 A13, A28, A42 --
          for an open-circuit.
        * Check contact resistance and oxidation (according to MMM A5).
        * Fix any problems with 31/71 before proceeding any further.
        * Repeat the ohmmeter test between the 3 pins and battery negative.
      - If any of the 3 reading is still incorrect, ie, not ~0 ohms:
        * You're going to have to wing it.
        * I suspect then you would need to check even more of the car's
          ground points (see the list in item 3).  I'd especially focus
          on the ones closest to the wires that you already have seen 
          were damaged.  That's one reason I highlighted some of the
          ground points that are on the right side of the car -- since
          I thought the car's wreck involved a collision on the right side.
      - Once you get the proper grounds for M44's A13, A28, A42 --
        ***if*** any of them were previously bad, 
        put the M44 back in and get everything
        setup like it should be, turn on ignition,
        then test again with Torque, Vol-FCR,
        Brick-Diag Free v0.0.6.6, and ElmBasic, and see if you can't clear 
        the P1618 with Torque (which would also probably clear the EFI-335).
        Then if Torque couldn't clear the P1618, try to clear the 
        Motronic 3-3-5 error with Brick-Diag Free and/or Vol-FCR.
        Also, try to clear the COMBI errors with Brick-Diag Free and/or 
        Vol-FCR.  It would be nice if you made records of anything
        which is different from what you've previously posted.
      - If either P1618 or EFI-335 still remain...
      - Turn off ignition.  [I'd take the key out of the ignition also.]
      - *** IMPORTANT ***
        *** Wait 2.5 min after ignition off so main relay has time to 
        *** interrupt its power supply.
      - After the main relay has interrupted its power supply...
      - Disconnect M44 ECM.
      - Turn off all equipment in car that consume battery power, 
        eg, interior lighting, radio, tools in OBDII port, etc.
      - This time we'll assume the M44 Connector A ground pins are OK,
        and continue the test sequence with the next step being adapted
        from the next step in the OTP 850 DVD diagnosis and fixing of
        EFI 335...
      - Using M44's connector B, connect ohmmeter between M44's B26 and ground
        to see if it reads in the 0 to 3000 ohms range.
        I believe you can check that resistance 
        from B26 (signal for MIL request from TCM) either:
        a) back to battery negative, or 
        b) from connector B's B26 to B28 (signal ground). 
      - If reading is *not* OK, ie, if M44 B26 to B28 resistance is infinite
        or is > 3000 ohms:
        * Check pins and sockets for M44 B26 and TCM B15
          for bent or damaged pins or sockets.
        * Check cable between M44 B26 and TCM B15 for
          short circuit to supply voltage, or open circuit.
        * Check for the common culprits of worn cables or 
          terminals which have come loose.
        * Disconnect connector at each end of cable,
          measure resistance to see that it is ~0 ohms.
      - If reading is OK, ie, if M44 B26 to B28 resistance is 0 to 3000 ohms:
        * Check pins and sockets for M44 B26 and TCM B15
          for bent or damaged pins or sockets, 
        * Check cable between M44 B26 and TCM B15 for
          short circuit to supply voltage.
          - Use both ohmmeter and voltmeter to isolate the short circuit.
      - ***If*** you fixed something in the TCM / M44 ECM signalling,
        put the M44 back in and get everything
        setup like it should be, turn on ignition,
        then test again with Torque, Vol-FCR,
        Brick-Diag Free v0.0.6.6, and ElmBasic, and see if you can't clear 
        the P1618 with Torque (which would also probably clear the EFI-335).
        Then if Torque couldn't clear the P1618, try to clear the 
        Motronic 3-3-5 error with Brick-Diag Free and/or Vol-FCR.
        Also, try to clear the COMBI errors with Brick-Diag Free and/or 
        Vol-FCR.  It would be nice if you made records of anything
        which is different from what you've previously posted.
    * If you haven't cleared both the P1618 and EFI-335 DTCs by now,
      then consider one of more of the following:
      - Isolate other grounding, short circuit (either to supply or to ground),
        or open circuit problems, then correct.  
        * This is the appropriate stage for disconnecting the ABS completely
          to see if it is contributing to the problem.
        * This is also the appropriate stage (if you haven't done it already)
          to check all your 11/xx grounds in the list provided in this post's item 3.
      - Replace one (or more) wiring bundles that seem to be the problem.
      - Get the OTP 850 Repair DVD so you can do research yourself 
        to shed greater light on the situation.
      - Continue to consult 98 V70 gurus on any of the many Volvo forums.

6. A newly defined EFI-335 from kwpd3b0_interpreter might eventually include the following highlights of everything else in this post:

EFI-335 -- Cable fault between AW 50-42 transmission control module (TCM) and Motronic 4.4 engine control module (ECM)
[P1618 (High), P1617 (Low/Missing/Faulty)]
[check grounds 31/71, 31/32, 31/33]
[see OTP 850 DVD: TP-2308032, pp275-280; TP-2318201, p43, p269]

7. Errata from English translation of volvopedia.de Motronic 4.4 Connector B table:

- B26 Neutral (ie, "Idling") column is better worded as "U = Ubat. NOTE! Other values apply if there are DTCs stored in the TCM."

esl_97_850_T5

[bmdubya1198]

The only ground I actually checked (or I even thought to look at) was the one under the pass. side headlight. I am now going to check all of those grounds.
I need to take the week to look over everything so I can get to work Saturday and run through testing the grounds and the ECM terminals, as that's when I'll have time to do more work and have some help with it. I'm also very interested in the transmission ground wire. I will definitely have to look into that.
I'll report back with my findings after testing, and if I discover anything else with the grounds from visually inspecting them.

[esl_97_850_T5]

bmdubya1198,

1. Then you've already done your most important ground check relating to EFI-335 (according to the DVD).

If I were you, I would reverify by checking with ohmmeter from M44 pins A13, A28, A42 back to battery negative to ensure resistance is 0 ohms on each of those M44 connector A grounds.

Once you see that's OK -- it probably is -- then I would skip the 31/32 and 31/33 ground point checks for the time being, since 31/71 is your '98 V70 ECU box ground point, and jump right in to debugging the 3rd item in the Summary:

Isolate short circuit to supply voltage (or alternatively an open circuit) between AW 50-42's TCM (aka 4/28 on wiring diagrams, aka ECU 6E)'s pin B15 to M44 (aka "the ECM", aka 4/46 on wiring diagrams, aka ECU 7A)'s pin B26.

If that doesn't bear any fruit, then I would look at all the other ground points to eliminate them as obscure sources of the problem. And I really would reconsider if my damaged cable fixes worked fully as intended. And I would try to determine precisely which wires had been damaged that I had fixed and which other wires run in that same bundle and which might have shorts or opens and be weirdly causing the screwed up AW 50-42 <--> Motronic 4.4 and screwed up COMBI <--> Motronic 4.4 communication.

2. Found a 1998 S70/V70/C70 specific wiring diagram -- 1998_S70_V70_C70_Coupe.pdf -- at MVS.

bmdubya1198, in most situations, surely that '98 SVC70 specific wiring diagram would be better for you to use vs. the 1997 850 wiring diagram and 1996 850 wiring diagram mentioned in previous post(s).

However, unfortunately, whoever created that 1998 SVC70 wiring diagram .pdf failed to include the 2nd page of the Components list (located near the end of the file) -- similar mistake to what was done for the 1997 850 wiring diagram available at MVS.

3. I did do some checking in that '98 V70 wiring diagram to see that the M44 ECM and AW 50-42 TCM grounds for the 1998 S70/V70/C70 both feed to the 31/71 ground point, similar to how they do for the 1997 850 (but not for the 1996 850).

I'll leave it to you to do any further research.

4. Another option for some 1998 specific diagnostic info is to buy at
https://www.volvotechinfo.com/index.cfm ... vice,parts:

Classic Service Information - Wiring Diagrams
Item: KCC51936 Page Count: 1
Models/Years
Contains one DVD disc will all Wiring Diagrams for models 1993 - 2004
Cost: $95

Engine Management System Motronic 4.4 (Fault Tracing; Gr. 28), 1998- Models S70,V70
Item: TP2323201 Page Count: 26
Models/Years
S70 V70 Sequential Fuel Injection 1997 ... 1998 Motronic 4.4
Cost: $24

I have neither evaluated either one of them, nor plan to do so. Just mentioning them since 1998 V70 specific diagnostics was missing from the OTP 850 Repair DVD.

5. Another option is to research that link from Ozark Lee that's mentioned at volvo_850_diag_links where you can download various sorts of Volvo documents. I researched that briefly today and found nothing pertinent to your case that you don't already know about.

6. The 1996 850 wiring diagram (linked to in my previous post) and the 1998 S70/V70/C70 wiring diagram mentioned in this post were brand new news to me. I wished I had read about them 3+ years ago.

Over and out. No need to respond. The baton has been passed to you.

esl_97_850_T5

[bmdubya1198]

I'm VERY happy to say that I have fixed my transmission! It turns out that the wires at the ECU box were not the problem. There is a square connector on the driver's side of the cooling fan that had a pin/wire not in all the way. I just messed around with it a little to put it back in, and it turns out that was the problem! I got in the car, turn on the ignition, and the up arrow light was on, as well as the orange light on the W button. I started it up, pushed the W button, and the light went off. I drove it around the block, and the transmission works great! It shifts smooth as butter, and it drivers great. It has a lot more low end power than my cousin's T5!
I connected VOL-FCR and BrickDiag, and both programs gave me XXX "Unknown Code" for AW50-42. I cleared it, and it didn't work on either, but it doesn't seem there's any issue as a result. I still can't clear the COMBI codes, but again, I don't see any other issues as a result. There does seem to be a bit of a battery drain, and there is a spark on the negative terminal when I connect it. I had all the doors shut and lights off, so I don't know where that's coming from. I'll continue to monitor that, and open a new thread if need be.
THANK YOU so much for all of your help, I couldn't have done this without all of this great information! Hopefully we'll be able to help someone else by having all of this documented here!