1999 S70 Cruise Control failure - Cabin filter success.

arrowrod · Post by **arrowrod** » 07 Jun 2011, 16:04

My new 1999 Volvo S70 Cruise Control doesn't work. I believe that the 1999 model works electronically through the ECU. So far, I have identified where the brake switch is (which research leads me to believe is the culprit most of the time). Now I am trying to find the Cruise Control relay (If one exists). I believe it is under, or beside the engine compartment fuse box.

I did have some success on the cabin filter. The repair database lead me to believe the you changed it from below the glove box. It turns out you access it from the engine compartment. 3 screws to lift the panel in front of the windshield on the passenger side. It's kinda "kool" that the filter fits loosely in its cavity. I shimed it with some one sided velco tape (the fuzzy side).

Interesting that the owners manual doesn't show where the cabin filter is.

Onward... Its a good thing I'm retired and have time to become a 1999 S70 Volvo expert. I have found a DVD Volvo S70 service manual on Ebay. It's on the way.

Post by **VCA** » 07 Jun 2011, 17:29

arrowrod wrote:My new 1999 Volvo S70 Cruise Control doesn't work. I believe that the 1999 model works electronically through the ECU. So far, I have identified where the brake switch is (which research leads me to believe is the culprit most of the time). Now I am trying to find the Cruise Control relay (If one exists). I believe it is under, or beside the engine compartment fuse box.

There's no fuse. The cruise system is totally run by the ECU and the ETM (Electronic Throttle Module)--check the wiring diagrams on the repair site if you'd like to take a look. If the car runs normally, then it's either the switch, or the ECU isn't happy with the condition of the ETM (assuming your brake lights aren't on all the time). My money's on the switch, but without VIDA and a DiCE or VADIS and a VCT2000, it's difficult to confirm 100% without just throwing parts at it.

arrowrod · Post by **arrowrod** » 08 Jun 2011, 04:43

Grrrrr...

My 'merican scan tool (in Top Gear parlance) is rubbish.

Any suggestions for a scan tool that duplicates the Volvo dealer for $100? Just kidding.
Any suggestions for a scan tool?

Will look at cruise control operation stalk.

arrowrod · Post by **arrowrod** » 08 Jun 2011, 12:27

Making progress...

Just down loaded the wiring diagram for the S70 1999 version (tried earlier in the morning and failed, 2 am).

Removed the turn signal, cruise control stalk and ohmed the cruise control. The increase speed (+) switch fails, but the rest of the switches work. Let me guess, a new stalk is $259. Will look it up.

Reviewing the wiring diagram, it appears that I have the Denso cruise control. (no cruise module in the fuse compartment).
It appears to be really simple. Cruise control stock, and brake-clutch. Then ECM - ETM.

I have 5 nonsense codes, P1027 P1021 P1081 P1029 and P1059? Looks like I'm going to get a EU702 code reader.

Car runs really well.

Post by **VCA** » 08 Jun 2011, 18:15

arrowrod wrote:Making progress...

Just down loaded the wiring diagram for the S70 1999 version (tried earlier in the morning and failed, 2 am).

Removed the turn signal, cruise control stalk and ohmed the cruise control. The increase speed (+) switch fails, but the rest of the switches work. Let me guess, a new stalk is $259. Will look it up.

Reviewing the wiring diagram, it appears that I have the Denso cruise control. (no cruise module in the fuse compartment).
It appears to be really simple. Cruise control stock, and brake-clutch. Then ECM - ETM.

I have 5 nonsense codes, P1027 P1021 P1081 P1029 and P1059? Looks like I'm going to get a EU702 code reader.

Car runs really well.

If the "+" fails to complete the circuit, that's why the cruise won't set I'm afraid--it's the "SET/ACCEL" button. It's part #9162455, about $77 from VolvoWholeSaleParts.com (one of this site's sponsors, tell 'em we sent you!) Do clear all codes and drive it around to see what sticks, seems like the poking around might've set a few...a generic OBD-II scanner can clear those codes. If you're going to get really nutso serious about diagnosing these cars electrically, getting a DiCE off eBay and a copy of VIDA is probably the best way to go. I think a Launch X-431 can also get the manufacturer specific codes for all systems including the airbag, in case you want something a little more universal. (All of these suckers are pretty expensive, though).

arrowrod · Post by **arrowrod** » 08 Jun 2011, 18:44

Well f-bomb me!

Measured the clutch sensor (2000 ohms, clutch out; 350 ohms, clutch in). Found a verification of the measurement on the UK volvo forum.

Noticed that the brake sensor isn't where it is supposed to be according to the wiring diagram on this site. But noticed that (what I believe is the brake light switch on the brake pedal) had a little slack. So I thought, drive it and pull the brake pedal out. Good guess, but wrong.

So as I was driving and cussing, I thought I would play with the + and - buttons on the cruise control stalk. + nothing (as expected). Pushed the - lever, whoa! Cruise control light pops on, we have lift-o... er, we have cruise control.

Mr. VCA is right on.

Post by **VCA** » 08 Jun 2011, 19:50

arrowrod wrote:So as I was driving and cussing, I thought I would play with the + and - buttons on the cruise control stalk. + nothing (as expected). Pushed the - lever, whoa! Cruise control light pops on, we have lift-o... er, we have cruise control.

Mr. VCA is right on.

Never knew hitting - would set it. On the newer cars, it resumes cruise at the current speed, rather than the set speed. So for now you can cruise and decelerate, but not accelerate

Post by **mikealder** » 12 Jun 2011, 03:41

arrowrod wrote:I have 5 nonsense codes, P1027 P1021 P1081 P1029 and P1059? Looks like I'm going to get a EU702 code reader

P1027 Throttle Body internal fault
P1021 Throttle Unit
P1081
P1029 Accelerator Pedal Sensor Fault
P1059

No info on the other two codes, just hope they are old stored codes and the ETM was sorted out prior to you getting the car - Mike

arrowrod · Post by **arrowrod** » 12 Jun 2011, 07:32

I got my son's newer code reader. P1081 and P0505. No CEL was set. The other codes I reported P1027, P1021, P1029 and P1059 appear to be figments of my scan tool's imagination.

P1081 is supposed to be immobilizer. I hesitate to even post this.

P0505 is supposed to be Assisted Air Control Valve (AACV) or Idle air control system.
On 1998 S70 there is a seperate air control valve. On 1999 this task is assumed by the ETM.

If I am reading the documentation from the scanner company"s web site, It takes two code settings in 40 heat cycles to set the CEL (what I call the service engine soon light).

I believe that my scan tool is obsolete.

Post by **VCA** » 13 Jun 2011, 06:15

P1081 is immobilizer communication/faulty communication (probably not a permanent code since the car does start sometimes)--probably the antenna ring given the number of failures we've seen with those. I hesitate to recommend this without a scan of the immobilizer module for any particular codes on it.

P0505 is indeed the AACV. You still have an AACV in your '99 according to VIDA. It's probably sticking or defective. Check all hoses (there's a hose in the middle of the air rail that the fuel injectors sit in, it goes back to the AACV on the driver's side of the engine) to/from the AACV for holes, loose connections, etc. I'm putting money on a stuck valve. It's part 1275634 and if you're not sure what it looks like, Google the part number and Volvo and you'll find a picture in image search. Is it worse when it's hot out?