No start electrical issue need help please(long post)
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Racer
Joined: Aug 2010
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From: Tyler Texas
I am going to try and post pics of the ignition switch and the ohm readings in question, again this is with the key in the run position only and only on these pins..
Last edited by larryu; Apr 25, 2012 at 09:56 AM. Reason: additional info.
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
When you rotate the switch thru the three positions (see that table on my CRUDE DRAWING ) you will have contacts that CLOSE. Closed is ZERO OHMS. When contacts are OPEN,,,,,,,,,, they read INFINITY/OPEN
A "SHORT" in the switch would be a reading between two terminals that do not normally read zero ohms or when the switch is in a known position.
When you turn the ignition ON,,,, do you see a BLINKING SECURITY LIGHT???
When you CLEAR ALL the DTCs and attempt to start the the engine,, what DTCs reappear??? Post those.
Bill
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Racer
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From: Tyler Texas
Bill thanks for chiming in. The security light only blinks when the key is out and the door is open. I ran through the DIC and try to restart the car just now and there are no codes after I cleared them. The only things I have noticed are the running lights are not illuminating and I can not hear the fuel pump kick on. Everything else seems to appear to be working properly. Except the no crank. All gauges, dash lights, and door controls work as normal.
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
There isnt really ONE SINGLE "Ignition Switch" schematic that shows ALL the contacts and circuits that they go to. There are MANY LAYERS that you have to go hunt down to figure out what is happening.
Heres the START part of the switch:
Heres the switch:
Heres the START part of the switch:
Heres the switch:
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Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Are you SURE that your engine isn't locked up????????
Larry,,, Do you have an auto or a 6 speed? If I were in your shoes,,, I would pull all the plugs and see if the engine will spin over. IMMEDIATELY! STOP trying to start it!!!!!!!!!
You have POWER to the solenoid which in turn, should spin the starter when it energizes. The Bendix is being driven into the flywheel/flex plate. Its NOT spinning.
NOT GOOD!! IF,,,,,,,,,,,,,,,,,,,, the engine is (for what ever reason) locked up,,,,,,,,,,, if you continue to engage the starter, you will eventually bust the starter off the block..... Ask me how I know???
Get those plugs out, have some friends carefully watch both sides of the engine and look for fluid exiting the spark plug hole (to pinpoint the defective cylinder/s) and crank that engine over. (Be on the safe side and do this!!!!!)
Good luck my brother!
Bill
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Racer
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From: Tyler Texas
Bill the motors will start and run time to time. This has been going on for a few weeks. If I jump the TDR relay with the key on it fires right of then dies like there's no fuel. I know the motors turning over free and easy by hand. This is an electrical issue not mechanical I 100% sure of that.
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If your SURE that it NOT MECHANICAL,, then there only one other thing it can be.
Check out this circuit. Some where in the chain,, is a poor connection that stops the flow of current to the LOW CURRENT side of the TDR.
The TDR initially works and for what ever reason STOPS.
Follow the flow of electrons from the Hot at all times from the fuse all the way to the BCM and see what component is failing..
Bill
Check out this circuit. Some where in the chain,, is a poor connection that stops the flow of current to the LOW CURRENT side of the TDR.
The TDR initially works and for what ever reason STOPS.
Follow the flow of electrons from the Hot at all times from the fuse all the way to the BCM and see what component is failing..
Bill
Thread Starter
Racer
Joined: Aug 2010
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From: Tyler Texas
Bill looking at the Diagram the only things that jump off the page that I don't have new at this point are the ignition switch that I did clean and the BCM. I hope the starter engage module in the BCM is not bad. I don't know how I would check that. Any ideas on that?
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You can eliminate things by jumpering. Start with the ignition switch. Get a good jumper wire and attach it to a known solid HOT source and apply it to the C5/C2 side of the CRK Fuse# 14.
When you complete the rest of the circuit, it will either do the same thing or crank correctly depending on if the ignition switch is causing the issue.
Is your car an auto or MN6?
BC
When you complete the rest of the circuit, it will either do the same thing or crank correctly depending on if the ignition switch is causing the issue.
Is your car an auto or MN6?
BC
Thread Starter
Racer
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From: Tyler Texas
Bill when I jump the TDR from red to purple it fires off. So looking at the diagram I need to check the yellow/black wire to see if I am getting current out of the TDR to the BCM. If I am, then chances are the started engage relay in the BCM is bad ? If this is so is there a way to reset the BCM or replace the starter engage relay without replacing the BCM itself ?
Last edited by larryu; Apr 26, 2012 at 10:51 AM. Reason: more
Thread Starter
Racer
Joined: Aug 2010
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From: Tyler Texas
Bill I just got home from work and started checking things again. I have found if I use my test light on the TDR and I ground my test light with the test light pushed into the yellow/black wire the car starts every time but dies like its running out of fuel. If I pull the test light out the. I am back were I started with a weak bump of the starter every time. I will post video tomorrow if this does not make sense.
Drifting
Joined: May 2010
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From: Pearland, TX
I think you are grounding the yellow/black wire through your test light when you do that. The grounding of that wire is normally done by the theft-deterrent relay control in the BCM when you start the car.
I don't think the TDR control in the BCM needs to stay continuously grounded to keep the car running though.
Maybe you have two problems? Faulty BCM and clogged fuel filter?
I don't think the TDR control in the BCM needs to stay continuously grounded to keep the car running though.
Maybe you have two problems? Faulty BCM and clogged fuel filter?
Drifting
Joined: May 2010
Posts: 1,482
Likes: 2
From: Pearland, TX
I think it's only there to prevent the car from starting when the input from the ignition switch is incorrect. I don't think it will cut the fuel, but I'm not sure.
You said that the fuel pump wasn't coming on though, right? That wouldn't be clogged filter.
You said that the fuel pump wasn't coming on though, right? That wouldn't be clogged filter.