1994 850 No start, no spark

Post by **jblackburn** » 09 Mar 2010, 22:26

The only other suggestion I have would be to start probing the voltages at the pins at the ECU themselves. I attached this, but you already have it if you have the service manual from the site.

pin voltage charts.pdf: (51.98 KiB) Downloaded 281 times

In particular, you'll want to check the grounds at A20 and A29, the control signal to the main relay,and the POWER STAGE (ignition coil) control signal from B13. That's the one I suspect - I would check these wires for continuity from the ECU to the coil.

B13 - Power Stage Control Signal (Ignition On) 0.15 V
Power Stage Control Signal (Engine Idling) 0.6 V

That said, if everything checks out OK, continuity & voltage-wise, I'd bite the bullet and replace the whole thing. Someone above mentioned they had a replacement they'd be willing to send you.

1994_850_owner · Post by **1994_850_owner** » 17 Mar 2010, 16:15

Thanks to jpgurley I am now the proud owner of three ECUs with the same part numbers and version numbers.

I put in the ICU and checked it and it came up 111. I prayed and gave it a whirl and it did NOT start. I checked A6 and I got error 314 again.

I cleared the code and put in the EFI/Engine ECU and the TCU. What the heck I had all three as a set and they all played together before. All codes were also 111. I tried to start it and to NO avail. A6 still shows 314.

I am now going to try and see if there is any voltage at the ICU pins and then ohm them out to the CPS and ground. I know that this is going to be tough to do without a breakout box, but I don't know what else to try at this point...

Does anyone have any ideas of what the three overload relays do- the ones with the "J" on them??? Someone mentioned in another post that he replaced one when he had similar problems and everything worked. He did not remember which one though....

Thanks again for all of you all's help and advice. I guess that I will keep plugging at this...

Don

1994_850_owner · Post by **1994_850_owner** » 17 Mar 2010, 18:39

OK. I went out and checked the wires as jablackburn suggested.
_______________________________________________________
In particular, you'll want to check the grounds at A20 and A29, the control signal to the main relay,and the POWER STAGE (ignition coil) control signal from B13. That's the one I suspect - I would check these wires for continuity from the ECU to the coil.

B13 - Power Stage Control Signal (Ignition On) 0.15 V
_______________________________________________________

I checked for voltage at B13 with the ignition key on and I received 0 volts. I don't know if this was because I had the ICU unplugged and I was checking at the connector.

I checked for continuity from B13 to the power stage unit and it was OK,

I checked A20 and 29 and there was 0 ohms to ground, and 0 ohms between both of them.

For the overload relay shown on the wiring diagram I checked for voltage at both sides of fuses 1, 2, 8, and 33- all OK.

The other two relays don't show up on the diagram so I don't know which one I was really checking out of the three.

I also ohm'd out all three wires going to the CPS and the ICU and they ball checked out OK too.

I will go to the junkyard tomorrow and check the CPS and try to get an OEM. While I'm there I will also grab the "J" overload relays as well as the fuel pump relay. Maybe even the Crankshaft positioning sensor because I replaced mine with one from Auto Zone- Duralast.

Anything else I should look for and try to get??

Thanks again for all of you all's help and advice. I guess that I will keep plugging at this...I've got a lot of time and money invested in this to give up now. It's only a machine right, and we are smarter than they are, right.......

Don

Post by **jblackburn** » 18 Mar 2010, 07:31

I checked for voltage at B13 with the ignition key on and I received 0 volts. I don't know if this was because I had the ICU unplugged and I was checking at the connector.

There should still be a voltage signal fed through that wire. I don't understand either. I wonder why it's refusing to output a voltage to B13. I would have thought a new computer would have fixed that.

I have no idea what the overload relays do, but if you can get your hands on them, hey, it's worth a shot. I would THINK it would shut down more than just the ignition coil though, but I could be wrong.

Get your hands on a Bosch cam position & crank position sensor from the junkyard as well. These cars are very picky about their aftermarket parts.

It's only a machine right, and we are smarter than they are, right

Haven't you seen I Am Robot? Or Terminator?

Post by **jpgurley** » 18 Mar 2010, 10:06

Hey Don,
I hate to say it, but I wouldn't trust the Auto Zone Cam Position Sensor.
I was a "Commercial Specialist" for AZ for four years and saw way too many bad parts returned.
Try a "known good" Bosch unit and see what happens.
JPGurley

1994_850_owner · Post by **1994_850_owner** » 18 Mar 2010, 21:09

Yea there is a GOD!!!

I went to the junkyard and picked up a CPS and a new fuel relay.

I out the CPS in and it had spark and did not send code 314.

I stopped and put the straws wirth of oil in each cylinder. It strated but wuould not stay running. I put the air filter box with the mass ais flow sensor connected and it would try to start butnot keep running while holding down the gas pedal to the floorand still quit. I tried a littel eyther and it stayed running a littlr longer. It was accting like it was not getting any gas to the railsthis was on the basnd new fuel pump relay from Volvu .I had a new relay I had pulled out of the car today at the junkyard so I tried it. It started up right away and purred like a kitten!!! So the new relay I got from NAPA that says Volvo on it is also NO good. I'm hoping that they give me my money back-even though it is an electrical part. Also that AutoZone will reimburse me for the CPSs

So for now on I will stick with OEM parts and the heck with these aftermarket parts. I will pay the $170 for a Bosch CPS verses the $139 from AutoZone. The heck with those Chinese and Japanese european want-to-be's. They just don't measure up!!!

Now what are the best plugs to put in after this. I have Autolite in now which have to be gapped to 28, The ones I took out were Bosch 3-prongs. And I have heard scuttle on NGKs and other Japenese plugs. Which are the best to use for a NA car ???

My next projects now are to flush out the tranny, clean the IAC, clean the PCV, flush out the brake lines, flush out the radiator, put in the new 192 thermostat and trmp sensor, clean the maf sensor, and think about doing the timing belt ( i have 132,000 miles right now), tensioner and pulley along with the water pump.The serpentine belt and tensioner and maybe alternator while I am at it. Oh, and have the A/C system checked out totally. I don't know about the fuel pump and regulator , The starter, solinoid and regulater all seem to be ok.

What about the Ho2 sensors, should I take them out ckean and R/R them too ???

What about the suspension, shocks, and struts- bushings and associated hardware. It handles nice know, but ...

And I guess that I will go in for tht fuel tank recall and check it out.

I hava all new tires and new front brakes and rotors, the back seem ok.

Does anyone know where in the states they do fuel injector flushing and cleaning??? I read a nice write-up on a guy over in Englad that does them for a great price,

So thanks everone for all of your help and advise in trying to solve my problem. I sure have learned alot fro this experience.

Now I have a lot of spare parts to aid in further troubleshooting.

Again I want to thank everyone who put in their inputs and opinings. I have learned so much about this car and hope to keep it for atleast another 132K miles I hope that all my woes will be able to help others along the way with similar problems.
Thanks you all. peace, and may better days always be ahead of us...

Don Phillips

Post by **jblackburn** » 18 Mar 2010, 21:36

Woah, lots of questions!

First of all, YAAAAAAAAAY! I kinda figured it might have been that in the first place, but I thought maybe after 2...one of them would have worked...Darn aftermarket parts!!! *shakes fist*

I loved my Autolites - I have since been running Bosch Coppers, as everyone reccomends, and I seem to have lost ~2 mpg. As long as you have them gapped correctly, it really doesn't matter. NGKs are great plugs in Hondas and Toyotas, but don't use them in a Volvo. Don't use multiple prong plugs unless they're the genuine Volvo kind - the Bosch 3-prongs are similar, but stay far away from the platinum-ii and platinum iv plugs.

Could these cars really be any more picky?

H20 sensors can be cleaned down with carb cleaner and put back in. They are a COMPLETE pain to get out though, but if you're feeling ambitious, by all means go for it.

Suspension issues are more of a "your call" thing at this point. New struts would probably help it handle bumps (and curves) better, but I have been putting mine off for fixing other things, and it still handles well. Then again, mine is 4 years newer and 30,000 miles past yours. Check your control arm rubber bushings to see if they are deteriorated and worn out - those are one of the most common things to go wrong. Tug on the tie rods & sway bar links. Neither should move. And lastly, check the spring seats under the hood. You should be able to grab the nut at the top of them with a wrench and the nut should NOT turn very far in either direction.

Fuel pump, alternator starter, etc...don't worry about them for now and save yourself the money. They'll die at some point, maybe, sure, but there's no predicting when, and they may be good for thousands of miles to come. As always, it's good to have a AAA membership with an older car.

Post by **jpgurley** » 19 Mar 2010, 09:13

Congrats Don,

I have found plugs other than the Volvo 3 prong plugs will cause a weird skip at idle in gear (at a stop light). Since they last so long, it's worth the $$$and you can get the from FCP Groton.

I second jablackburn "Darn aftermarket parts!!!!

Enjoy the ride and thanks for helping all of us go through the struggle with you.

I agree, There is a God and He is good.

JPGurley

1994_850_owner · Post by **1994_850_owner** » 19 Mar 2010, 18:25

Again, thanks everyone for all of your help, advise, and prayers.

I really have learned alot along the way. But I wouldn't have been so bold without you all's help and support.

Here's hoping and praying for many good years to come.

I will see you all on the forums.

Thanks again,

Don

1994 850 No start, no spark

Re: 1994 850 No start, no spark