electrical gremlin

RenegadeT

RenegadeT

no shirt,no shoes,no dice
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Mar 24, 2005
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Stokesdale-Greensboro
Help me figure out why my truck is possessed. Classic electrical problem, this only happens periodically...

With the key off/out, some of the key-on functions work, ie radio, wipers, power windows. Whats really weird is the fan will not work when this gremlin pops up, and yes the fan works fine with the key on.

I first noticed this when the radio would pop back on after shutdown as I was exiting the truck. Seems like it started happening weeks, possibly even a couple months after I installed pyro/boost/fp gauge on the A-pillar. I don't think I tapped a wire wrong but who knows. I used a fuse tap off an ignition-on circuit for my pyro power and a fuse tap on the dash illumination fuse for gauge lights. My truck has the premium Infinity sound system with the goofy (or so I've read) tweeters wired directly to the amp or something. The A-pillar tweeter worked before gauge install, but not after.

Where do I begin the troubleshooting process? This is my '98 12V Dodge CTD, with dual batteries.
 
Does your truck have the retained accessory power? Like when you cut the truck off did those accessories stay on until you opened the door? If so it may be something there.
 
jeepn-jason said:
Does your truck have the retained accessory power? Like when you cut the truck off did those accessories stay on until you opened the door? If so it may be something there.
Click to expand...

Nah, it doesnt have that new fangled crap. Door open/door closed, it doesnt seem to matter, the wipers and radio still have power to them.
 
should my wipers work with the key in the accessory position? Mine do...I'm thinking there might be a short somewhere in the ignition switch or linkage between key tumbler and ignition switch, where it thinks it should be in accessory mode?
 
Gremlins evolve under water....they turn from cute lil furry creatures to scary hideous monsters....


Spray everything down with a garden hose
(Sorry I have nothing useful to add)
 
Im not sure on the dodges, but GM def works off of ACC. The wipers that is. Does the switch still feel the same, like resistance when you start it?
 
Sounds like ACC to me, but with a few extras. Like the wipers for instance. I think i has to do with the ignition on tap to the fuse. What amp is it?
 
bump...
Finally got a lil time to check this out. After letting my truck sit for 5-6 days, I had a no-start condition, both batteries were run down to about 9V. So I charged them up to 12V, reinstalled one, connected the positive leads, left the negative unhooked. I put my multimeter inline between the negative battery post and the negative ground cable and found 2.35 amps.
I started pulling fuses. When I pulled the #12 (10A) I.O.D. (I think its Ignition-On Draw), the multimeter dropped to 0.01 amps. Is that enough to drain 2x 12V batteries (both checked out OK at AutoZone) in 5-6 days, or am I still looking for some intermittent accessory-type short. When I did this test, the key was off, and the accessories were not working. If you read my first post, sometimes the accessories (radio/wipers, etc) work with the key in the off position.
 
ok I lied....Ill try.
You have something that draws power in accy that is not obvious. Electric boost pump, heat strip...could be any of a million things installed by a PO, or a factory.

BUT your problem 99% likely anyway is your ignition switch is going out and not braking the accy internal contacts int he off position. IN OTHER WORDS you turn switch off and accy power stays on, you have experienced this as sometimes radio wipers etc work.

My firs fix would be a new ignition switch in the column, if that doesnt solve it, you may have an abrasion caused short/backfeed in the column harness.
 
SkyHiK5 said:
ok I lied....Ill try.
You have something that draws power in accy that is not obvious. Electric boost pump, heat strip...could be any of a million things installed by a PO, or a factory.

BUT your problem 99% likely anyway is your ignition switch is going out and not braking the accy internal contacts int he off position. IN OTHER WORDS you turn switch off and accy power stays on, you have experienced this as sometimes radio wipers etc work.

My firs fix would be a new ignition switch in the column, if that doesnt solve it, you may have an abrasion caused short/backfeed in the column harness.
Click to expand...

thanks skihi, that's about what I was thinking. wtf is a electric boost pump though.

2.35 amps, is that too much draw thru the IOD fuse? Would that kill 2 batteries in a few days?
 
RenegadeT said:
thanks skihi, that's about what I was thinking. wtf is a electric boost pump though.
2.35 amps, is that too much draw thru the IOD fuse? Would that kill 2 batteries in a few days?
Click to expand...


Im not sure Ive ever seen one on a pick up, but some equipment that comes through our shop has an electric fuel "boost" pump that basically primes the lift pump.

2.35 amps continuous draw would certainly a couple 800CCA batteries down to too low to crank in a few days.
 
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