Seanam

My 2007 Ford Mustang 4.0L will not stay running. The car turns off whenever the engine fan turns on, or you turn on the AC, the headlights, the parking lights, or the right turn signal. Left turn signal bogs the car down, but doesn't shut it off. Dashlights, heater fan, brake lights, interior lights, radio, etc., all work fine. The connector under the Engine Fan Relay in the BEC is burnt, but the relay seems OK and the fan turns. I'm not sure where to go from here. Has anyone experienced a similar problem?

bl817

take a look at the smart junction box in the passenger side kick panel. check all the connectors. I'm willing to bet its getting wet when it rains or carwash, and over time its corroded big time. pull the sill plate off, then the kick panel. 10mm bolt holds it to the body. pull it off and inspect it. good luck

07 Stang

Seanam, it has been raining a lot here in VA lately so if you drive or park your car outside in it, the likely culprit is probably a wet Smart Box as bl817 suggested. Feel around the passenger carpet area to see if it is wet or damp. There are a number of threads on this unfortunate subject. Perhaps you may be able to fix it yourself. Let us know what you find.

Seanam

Thanks so much for the replies! I checked the SJB, all the fuses, and began tracing the wiring out of the BEC. Turns out that the problem was the ground connection for the headlight wiring harness. Cleaned that up and tightened it down and everything is working again. I ran across a post from another member who was having similar problems that put me onto the solution.

https://mustangforums.com/forum/4-0l...ing-issue.html

Thanks again!!!

movielover40

Glad it's fixed.

07 Stang

Good Job! Glad you were able to resolve it.