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Electrical Issue, Possible Computer failure... HELP!

1470 Views 8 Replies 3 Participants Last post by  Hellraiser456
I am reaching out to you guys in hope of coming up with something I have not thought about or tested yet.

This car is an 08 GT with Saleen supercharger. The intercooler pump is mounted near the bumper on the passenger side of the car. The wiring for the pump comes off the HOT side of the CJB in the engine bay, to the pump and then the pump is grounded to the chassis; so it is running with key on or in accessory.

Now my problem. Yesterday I barely bumped a curb, but in the process broke the wire harness that goes to the intercooler pump and shorted out the leads at the pump (which had a 30 amp fuse in it). The car immediately died when this happened; no hesitation or anything.

Now, when you turn the key to the on position all the accessories get power but the gauge cluster shows every alarm and warning as if it isnt receiving data from the PCM, similar to what you see when loading a custom tune when the computer reboots. Using my SCT x3, it gets power from the OBD-II port but cannot access the computer or read any codes.

I checked and test the fuses in the CJB in the engine bay and they all look good. Double checked for shorts, and pulled the fuse on the bad harness going to the intercooler pump with no luck. I fear the computer (PCM) may have been nuked, unless there is something in the PAT system that would stop the PCM from even booting.

I would really like to not spend $1100 on a computer replacement plus the hassle and money of having my SCTx3 unlocked and reloading all my tunes.

Let me know if any of you have seen or heard of anything similar to this. I will probably work on it some more today and get any pictures if anyone needs to see.

Thanks in advance for any help!
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Check to see if your X3 device will communicate with the ECU.
I did right as it happened. No go. Won't unlock the ecu
The SCTx3 will power cycle the computer in an attempt, but doesn't work either
Hey. I think there may be a chance you may have hurt something. I know those sjb's are sensitive and short circuits are worst case scenario.

Did you hook up the pump directly to the cjb or did you use a control circuit to control the pump and hook the pump up to the battery? I feel like this should have a relay somewhere. If there isn't then that isn't good. Im a little confused on how exactly this pump was set up.

Double check fuses. Use a continuity check from an electrical meter. Check pump relay.
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-- double post please remove
Dyno Joe out of Houston did the original install of the supercharger. Can't seem to get a hold of him to ask about the intercooler wiring. Trying to find a relay. Wires going from engine bay to back of the car it looks like. Trying to trace the wiring out.
So I found an install manual for a Saleen on an 08. The power for the intercooler pump comes from the Smart Junction Box pin 36 in the passenger kick panel. See if this leads me to what I need.
So for pin 36, it should goto the relay, then to ground. Im assuming that pin 36 is an ignition power point. This would be the control circuit. Then the actual power for the pump would come from the battery, to the relay, then the pump, then to ground.

The relay could realistically be located anywhere on the circuit, but i would be checking around the battery, engine bay fuse box, and the pump. There may be a spare spot for it in the engine bay fuse board. They generally look like small black boxes with at least 4 pins. Typically they plug into a socket, to which the connections are made.

Once again im not a super charger professional, but i still think that if there is no relay, and a short did occur, all that current would go through the sensitive electronics of the sjb, then to the point of the short, which would "let out the magic smoke" typically. A relay isolates the power circuit so the worst case scenario would be burning the relay, which are cheap and easy to replace. It also allows you to use a significantly lower fuse on the control circuit, so if a short occurs on the control circuit, less current will pass. Considering that the front of a car is the most likely place for mechanical damage, i would be installing a relay for anything mounted up front.
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