What the Heck is going on?

[Firemed57]

Hi Guys,

My truck has been acting a little suspicious and may be an electrical issue. The dash warning lights for the TPMS, door ajar and brake come on, beep and go back off. It seems to cycle, but not consistently. I have also noticed that the headlights do not turn off while parked, the ac/heated seat buttons do not work and the liftgate will not open, and the turn signal indicators just blink in a slow inconsistent pattern.

I have checked the fuses, got a new battery, checked the alternator and now I'm afraid its either a hidden fuse, some sort of module, or the GEM.

Any ideas?

I did find a thread for door ajar that pointed at the radio control module...maybe, but i have an aftermarket Alpine unit.

Also, I plugged in a cheap aftermarket phone charger - could that be?

Thanks,

John

2008 Expedition EL Limted 4x4

 

[Adieu]

Poltergeist? Gremlins?

...Russian hackers??

 

[Firemed57]

Haha. Haven't heard poltergeist in awhile. Still a little scared. Crazy problem huh?

 

[The Swagonmaster]

I heard of one guy that hooked his battery up backwards and got some unusual results. Said that the radio started listening, the headlights would cast shadows and the horn sucked instead of blowed! ;-)

 

[The Swagonmaster]

Humor aside, it sounds like a broken wire / loose connection type of a thing. First look around under the dash to see if there is any evidence of someone doing any wiring work, then pay attention to any symptoms that come together. One that might happen is the door ajar light and the rear door acting differently.
The owners manual will tell you what the various fuses power up which might point to a good fuse that has a loose connection and works just fine as long as it has a connection.

 

[Firemed57]

That's funny. I like it.

Appreciate the humor and the possibilities swagonmaster. Is there more fuses hidden somewhere besides the kick panel and engine compartment? Do you think relay or module?

 

[stamp11127]

You can forget the fuse idea as the source of the problem. When you trip a circuit breaker at home does the circuit still work on and off?

 

[Firemed57]

No sir, it's a dead circuit. But i am interested in loose connections. I just got back from traveling so I will start digging tomorrow and let ya know.

Thanks

 

[Firemed57]

didn't see anything obvious, perhaps a relay? how would I check that or the stereo?

 

[SMichaelG2]

I would look up the wiring diagrams and see if all those things have a common ground. Ground connections easily can cause the problem you are describing, so either go spend an hour digging through the diagrams looking for one in common, or go tighten every ground connection you can find under the dash. I am not familiar with the computer systems on these trucks enough to tell you if all those things route through the body control module. Electrical gremlins are my worst fear in vehicle repair. Good luck!