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Question Early 944 - No voltage at ignition solenoid wire.

Hey Guys,

New to the Forum and looking for some guidance on an early 85 944 starting issue.

Background:
Car has been resting in a garage the past 10 years. After getting it all back together (clutch repair) I have run into this starting issue.

New Battery, Starter verified, all electrical contacts cleaned.

When I turn the ignition switch on (ACC) I get all the dash lights and things look good. When I attempt to start the car I get nothing, no click and no voltage to the ignition lead wire going to the solenoid.

If I use a remote starter button, I can start the car with another person "cranking the key" simultaneously with me pushing the remote button. So I have the fuel pump working and everything is fine once it's running.

Could there be an issue with the ignition switch itself that would affect it's ability to give power to the solenoid ? Even though it activates the fuel pump etc...

It doesn't seem like I have a bad ignition switch since it is doing all the functions of a switch except sending voltage to the solenoid.

Could there be a relay that is bad or corroded that is causing this issue ?

Thanks for your time,

Bimmerod
Old 05-02-2017, 10:53 PM
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???

Quote:
Originally Posted by 944 Ecology View Post
Bad starter contact in the ignition switch, or bad connection between that contact and the starter solenoid.

No relays involved in the starter circuit.
I replaced with the ignition switch and nothing changes. The key turns on to acc and then the Fuel Pump activates when in the crank position.

I have 12 volts to the blue wire when at acc at the connector next to the firewall and then 12 volts to the red/black wire when in the crank position.

I have checked continuity between the blue wire from the firewall down to the solenoid and that checks out.

Am I supposed to have 12v to the blue wire on the solenoid while cranking ???

Let me know your thoughts,

Bimmerod
Old 05-21-2017, 01:18 PM
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Quote:
Originally Posted by 944 Ecology View Post
Exactly. That is what triggers the starter to do its thing.
Well I have no idea why I'm not getting voltage to that wire while cranking.

I have continuity through the wire all the way from the switch plug.

I am not sure what else I can look at ????

At the firewall connector, I have 12v at the blue wire while the ignition is on. I then get a bright 12v on the Red/Black wire while cranking with my light.

Of course I always have 12v to the red/black wire at the starter. But for some reason I do not have or cannot get 12v at the blue wire while cranking or anytime for that matter.

Thoughts ???

Bimmerod

Last edited by Bimmerod; 05-21-2017 at 04:06 PM.. Reason: spelling
Old 05-21-2017, 04:05 PM
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What is the color of the "Blue Wire" at the ignition switch ???

That way I can trace it under the dash to see if the wire is not broken or eaten by rats
Old 05-21-2017, 05:47 PM
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Well I looked for any damage to the wire ans cannot see anything broken or cut.

I also tried the alarm bypass just to see since it looks like that "Blue Wire" goes to the Alarm Module.

Unfortunately no change for anything I have tried.

The car will not crank, no matter what.

Starts and runs with the remote starter if someone turns the key to the crank position simultaneously.

Another weekend with nothing resolved
Old 05-21-2017, 09:00 PM
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I guess George Beuselinck (944 Ecology) erased all of his amazing pearls of wisdom from my thread.

You would think after 1900+ posts he would have something to share besides sarcasm.

But I digress....

I looked at the wiring diagram and see that the Red/Black wire coming from the ignition switch feeds the circuit. I just can't seem to find the link between that wire and the alarm relay (blue wire) that goes to the solenoid.

If I link that wire directly to the blue wire (at the connector by the fuse block) I can start the car with the key.

If anyone other than 944Ecology has some ideas, that would be appricated.

Bimmerod
Old 05-22-2017, 10:36 PM
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Still trying to figure this out.

Nothing will make it crank no matter what I try or check.

I am out of ideas......
Old 05-28-2017, 01:32 PM
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Well, does the fuel pump come on? The DME will not energize the ignition coil or the DME relay without signals from the speed and reference sensors. I am confused by your post about the remote start crank thing. What are you bypassing with that?
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Last edited by Bradical; 05-28-2017 at 03:34 PM..
Old 05-28-2017, 03:32 PM
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Quote:
Originally Posted by Bradical View Post
Well, does the fuel pump come on? The DME will not energize the ignition coil or the DME relay without signals from the speed and reference sensors. I am confused by your post about the remote start crank thing. What are you bypassing with that?
Yes, the fuel pump activates in the crank key position. I can even start the car with the alarm module not even plugged in. It just involves turning the key to the crank position while pushing the remote starter button like described above.

The car idles smooth so it would appear all things are working. No warning lights on the dash, nothing out of the ordinary.

I need to figure out which ignition switch wire(s) energize the blue solenoid wire. That way I can try to trace it back to look for any obvious damage.

I have looked at the wiring diagram and frankly I can't seem to even find the blue wire info. I definitely can't find any wiring info for a car with a factory alarm.

It just doesn't make any sense on why it does everything except crank?

Bimmerod
Old 05-28-2017, 04:22 PM
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Ahh, I follow. The ignition coil's +12v isn't interrupted by the DME, the DME actually provides the negative pulse on the coil from pin 1 on the DME harness, and the blue (I am assuming) +12v wire should come from pin 15 on the ignition switch. If you replaced the switch and there was no improvement, but jumping out this wire allows the car to run I would assume that you have a melted wire somewhere under the dash. I don't have any experience with the alarm module, but I thought it interrupted the ground signal to the DME relay and the ignition coil (pin 1, pin 20) but I could be wrong.

If I were you I would see if I had +12v on the ignition switch in RUN, and if you do you know it MUST be interrupted somewhere.
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Last edited by Bradical; 05-29-2017 at 05:52 AM..
Old 05-29-2017, 05:49 AM
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Also, this document (I know its for the turbo) is extremely helpful for troubleshooting starting problems.

http://www.arnnworx.com/download/DME_KLR_Test_Plan.pdf
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Old 05-29-2017, 05:59 AM
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Lightbulb

UPDATE 5-30-17 !!!!

I made it to the junkyard to look at another 944 to try to figure out what was installed wrong. After looking at the car I noticed that there was no "blue wire" going to the starter and in fact the "blue wire" was actually going to the alternator.

So it appears that I had the harness backwards after putting the motor back in the car. In my defense I wasn't the one who took the motor out
I mean they both have a small and large eyelet connection but I should have known that the large Black wire should have went directly to the starter since it has to provide maximum juice.

Sooooooo, after switching the harness back to how it supposed to be, I am now able to crank the car with the key but it will only run for a couple seconds.

After some troubleshooting I have realized that I can make the car keep running by putting a 12v lead to the Red/Black wire (white connector) leading to the DME/ignition.

Of course I have to use my remote starter button in order to crank the car while someone else tunrs the key so the fuel pump primes the fuel rail.

Have I fried my DME by running it with the harness reversed ????

Just when you think you got it figured out, something else goes wrong :'( :'( :'(

Thanks in advance for your thoughts,

Bimmerod
Old 05-30-2017, 01:20 AM
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It won't keep running if the DME is completely fried. If it runs for a little bit and stops, it could be your DME. Sounds like the wiring to your DME & Fuel pump relay isnt right.

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Old 05-30-2017, 07:24 PM
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Have you tried jumping the DME relay? Pop out the relay, Hook the battery input to the computer power and to the fuel pump. You'll instantly hear the fuel pump turn on. Crank it, and it should start. You'll have to pull out at least one of the jumper wires to get the car to stop.

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Old 05-30-2017, 07:27 PM
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Yes, I have tried to jump the DME Relay. The symptoms do not change, the car runs for a couple seconds (basically while cranking) then dies once the key is released from the crank position.

It seems to me that the only thing left is the DME itself. That is the only way I can explain why providing 12v to the Red/Black wire will keep the car running. As soon as I unhook the 12v lead from that Red/Black wire the car will die.

So the question remains, what could be the issue with that scenario ???

In normal operation there is only 12v at the Red/Black ignition wire while in the crank position. As soon as you release the key there is no more voltage there.
It doesn't make any sense why maintaining 12v to that wire (at the white connector) will keep the car running ???

Bimmerod



Quote:
Originally Posted by DeadPorsche944 View Post
Have you tried jumping the DME relay? Pop out the relay, Hook the battery input to the computer power and to the fuel pump. You'll instantly hear the fuel pump turn on. Crank it, and it should start. You'll have to pull out at least one of the jumper wires to get the car to stop.

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Old 05-30-2017, 09:28 PM
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Do you know where the red/black wire goes? I'm not familiar with it. If it is power to the DME relay (pin 30 I think), then it needs to stay on. That would be an issue with the ignition switch. Just jumping the relay will not solve the problem if there is no power to jumper. Can you look at that pin on the relay? You can do it with the relay out. It should always have power, even with the key out.

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Old 05-30-2017, 09:55 PM
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Sorry, more than just an issue with the ignition switch. Pin 30 is supposed to go the battery. I don't have a very readable schematic, so it's hard to tell.

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Old 05-30-2017, 09:58 PM
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Probe around the DME/Fuel pump relay. If this relay is behaving properly, then there is probably something wrong with your DME. I had one die when I tried to start the car with one of the ground wires removed. I have a thread on it somewhere. I checked everything, hoping that the DME wasn't fried. I was able to try a known working one and the car started up.

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Old 05-30-2017, 10:04 PM
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That being said, if you can put i n some sort of switch or relay to force what you are doing, you have a working car... ;-)

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Old 05-30-2017, 10:06 PM
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Quote:
Originally Posted by DeadPorsche944 View Post
Do you know where the red/black wire goes? I'm not familiar with it. If it is power to the DME relay (pin 30 I think), then it needs to stay on. That would be an issue with the ignition switch. Just jumping the relay will not solve the problem if there is no power to jumper. Can you look at that pin on the relay? You can do it with the relay out. It should always have power, even with the key out.

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Yes, I have 12v at pin 30 on the DME relay.

Of course I can puit in some switch to "hot wire" it but I prefer to actually figure out what is causing this issue.

I will try to locate a known working DME to see if this resolves it.

Maybe I fried it by having the Y-Harness backwards

Bimmerod
Old 05-30-2017, 10:19 PM
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