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Old 07-23-2017, 04:59 PM   #1
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Brake lights fuse blowing

Stella is still making me shout! Brake light fuse blows immediately. I have installed a new switch, no joy there. Brakes light bulbs and holders are ok; switched to LED.

Fuse still blows with the switch plugged and the brake lights unplugged. So, what is connected to the B7 fuse that could be blowing it out? I don't have my manual here with me to spend time studying the wiring diagram.

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Old 07-23-2017, 05:25 PM   #2
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Cruise control.
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Old 07-24-2017, 04:06 AM   #3
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Where is the CC module in the car?? Any harm unplugging it and starting the car??
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Old 07-24-2017, 01:32 PM   #4
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No module. Best thing to do is to test the fuse clamps to confirm if there is a short to ground (disconnect both tail lights first), then report back.
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Old 07-31-2017, 05:44 AM   #5
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Lots of fiddling yesterday and thought we had it fixed. Too go to be tru... We worked under the dash with the switches on the clutch and the brake pedal. The brake switch is new but the red clutch switch is original.

We pulled the clutch switch, disassembled and cleaned it. It was quite dirty and corroded looking inside. Reinstalled, no change. Fuse still blows more or less immediately with key on (KO). Unplug this switch and the brake light switch. fuse doesn't blow KO. Connect clutch switch and fuse is still good. Start working with a jumper on the brake plug, we get lights no fuse blown. Connect to the black/red with for the CC and we get fuse blown KO.

We figure it has to do with the cruise system, maybe in the steering column. We pull the Bk/Rd connector from the switch and all seems to be OK. Test, test, test... All seems OK. Go for 20 minute ride in town with lights and traffic; all OK. Go back to shop, button up anything loose, head to home all OK. Go out to the store 6 hours later, fuse blown with KO. :-(

Back to the wiring diagram:

The BK/RD wire does go from the brake switch to the engine management unit as well as the ABS system. I can guess that the ABS pump could have a short inside that is blowing the fuse. I think it's more likely in the steering column.

Any ideas???

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