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2008 TB Fuse 13

2K views 9 replies 3 participants last post by  Scottpia 
#1 · (Edited)
Hopefully I am in the correct forum. 2008 TB keeps blowing fuse 13 immediately after replacing. Cig lighter and acc plugs never used. Any suggestions? Also pulled a P1682 before the fuse blew.
 
#3 ·
P1682:
there are 2 ignition 1 voltage circuits supplied to the engine control module (ecm) computer. The first ignition circuit is provided by the powertrain relay, through a fuse. This ignition 1 voltage circuit supplies power to all the internal ecm circuits associated with the throttle actuator control (tac) operation. The second ignition 1 voltage circuit is supplied by the run/crank relay through a fuse, and is used to power the remaining internal ecm circuits. If the ecm detects a voltage difference between the 2 ignition 1 voltage circuits, dtc p1682 will set.
Fuse 13 is the cigarette lighter and should be an entirely separate issue most likely a problem with a wire shorting in the harness.
 
#6 ·
Princej99................No abnormalities with the car running or starting. Only abnormality is that a check engine came on, when I hooked up the scan tool, it would not function. Changed fuse 13 and it worked and the light went away. Blew the fuse again a few minutes later. went to replace the fuse again and bamm popped immediately.
 
#9 ·
Stupid answer first - I assume you have been trying a 20A fuse in the cigarette lighter. And I believe fuse 13 is what supplies power to the OBD connector to power the scan tool.

Autozone has free wiring diagrams -
Autozone.com/Repair help/Vehicle Repair Guides/Wiring diagrams

It seems you have two problems and neither is affecting drivability. Clear the P1682 code. If it doesn't come back then that problem is solved. :excited: If it comes back and you've replaced the IS 3 times already, they you probably have wiring harness/connector issues. :sadcry: Oh, wait, you can't do that because fuse 13 keeps blowing. ARGH!!! OK, I think you're going to have to fix the cigarette lighter first.

I would be printing out some wiring diagrams and checking wiring in both the cigar lighter and ECM voltage circuits simultaneously depending on what contortions I had gotten myself into to get to the wiring and connectors. Since both are coming from the underhood fuse box I might try taking that out first to see what the wiring looks like underneath. Or, since you said the scanner worked the first time but then 13 blew, I might look for an issue right at the OBD connector which you wiggled when the fuse started blowing continuously. It would help to have a small 12VDC light and put it across fuse 13 terminals as you wiggle things. You want the light to not be on.

That's a start and it might be easy and it might not. Feel free to come back with results.
 
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