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V1 Anti Theft Re-engaged, Blowing ECM fuse and ignition fuse on BCM

K
I am a little confused by what you are saying about checking the ignition switch, is that the other connector at the back of the ignition? I thought we were just testing the vats connector. I will go test that one now if that is what you meant.
 
G
We are trying to work our way back up the chain. We know that we are not getting +12v at the BCM and TDM where we are supposed to. This comes from the ignition switch. You should have one +12v feeding the switch at all times. When you turn the switch, it distributes that +12v to the pins that we are looking at on the BCM and the TDM, plus to other locations. Now we need to find where we lose the +12v.

Based upon a one getting a +12v reading from battery + to pin 2, I think you have a short to ground somewhere between the switch and pin 2/c8. This likely shot a fuse that feeds the switch, but we are working our way toward that. And if true, you will have to find the short to ground. But one step at a time.
 
G
I am a little confused by what you are saying about checking the ignition switch, is that the other connector at the back of the ignition? I thought we were just testing the vats connector. I will go test that one now if that is what you meant.
Ignition switch is basically the key. Labeled as ignition switch on the diagram I marked up. Not sure about the "other connector at the back of the ignition" part of your question.
 
K
Ok so I checked for any obvious cuts or blackened parts along the harness from pin 2 to c8 and couldn't find much. I also checked c8 again and when touching c8 and touching ground there is no voltage but when touching c8 and touching positive there is battery voltage.

In terms of the ignition testing what exactly do you want me to test? I have tried multiple different keys. Do you want me to somehow test the entire unit? If so I do not know how to go about doing that.

Also I will say that your help is very much appreciated and I am sorry if I do not understand some of the things you are saying. I really am trying to work through the issues but I am an amateur when it comes to wiring so it takes me a little longer to figure some things out.
 
K
So for pin 1 on the vats connector that one is red and white and is getting battery voltage. But for the connector behind the ignition:
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The wire on the far right does not have battery voltage. It looks somewhat red and white to me but I am also colorblind so I am not sure.
 
G
I’ll be a couple hours before I can weigh in anymore on this. Give me the wire colors on the green connector, in order so I can confirm the connector when I get home.
 
K
Ok this is going to be using the same picture as a reference and I am moving right to left for those wires.
Red and white
Yellow or maybe like a tan wire
Possibly dark green
Full white
White with black stripe
Again, I am bad with my colors so these are more guesses as to what they are.
 
G
If you are colorblind, it will be helpful to know. That way we can make sure we are talking about the same wires.
That should be the correct connector, although later model has brown instead of green for the middle wire. I think yours in brown also since the diagram we have been working off of shows brown.

Two test.
1.Check and see if you get voltage on the brown/center wire with the switch off and in the run position.

2. disconnect the connector and see if you get continuity between the pin for the red/white wire and the pin for the brown/center wire, (on the switch itself, not the connector)

If this isn’t clear, go ahead and ask the questions.
 
G
I just re-read your post #46. Disregard my previous post. I even missed the part about being colorblind.

If you don’t have power on the red/white wire on the green 5 wire connector ( 5 wire connector in your picture, wire beside the empty slot) that is the problem. We now have to work that wire back towards the battery side.

Do you currently have a good fuse in ignition switch/pk3 on the bcm? The 2a fuse? Don’t just visual check, either pull it and check continuity through it or probe the openings on top and check for voltage if your probes are small enough.
 
K
So the 2a fuse was blown, I am not sure when it blew because I replaced and and tested it multiple times and thought it was good but it was not. Tested the red and white wire and now I am getting battery voltage to the red and white wire.

I checked continuity on the switch itself with the connector unplugged between the farthest right pin and the middle pin and I could not get continuity.

I am unsure by what you mean of the first test you said. I get no voltage from the brown center wire when it is connected to the ignition and when it is unplugged I also get no voltage.

Edit: I just checked the 2a fuse and it blew immediately. I think it blows when I turn the key because plugging in the battery does not blow it.
 
G
You have a short to ground after the ignition switch. We really need some additional diagrams for you model, but we can try and trace it anyway. Disconnect the TDM and C2 and C4 connector on the BCM. With the switch disconnected, check all of the wires (except the Red/White) for continuity to ground.
 
K
I checked continuity to ground. I am assuming when you say C2 and C4 connectors those are the multiplug not pins on one of the multiplugs. I was not sure exactly which multiplug C2 was as they are identical but I was pretty sure it was the vertical one and there was no continuity to ground.

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Vertical one to the left.
 
G
I don’t have the diagrams for your model and the call outs are different. I think that is the c2. So you checked all of the wires at the switch and none of them were grounded?
 
K
Yes that is correct none of them were grounded. I also confirmed it was the c2 switch by testing continuity between the black and white wire to pin 62 on C2 and they have continuity.
 
G
Plug the modules back in one at a time and see if any of the wires are then grounded. All of the modules may indicate that they are grounded and we may have to try something else. I don’t know exactly what the modules are doing inside so they can appear grounded. We may just have to put another fuse back in and see what module makes it blow. But first try checking for ground with the volt meter.
 
K
When plugging in c2 the white as well as black and white wire have ground but they have some resistance to ground. When plugging in the c4 the red and white as well as yellow wire get ground with resistance. The brown center wire gets ground with no resistance.

with just the c2 unplugged and the key turned to run, the dash lit up for a second then the fuse popped.
 
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