Jimmy turn signal problem not yet covered..

I removed the dash on my '96 Jimmy to fix a heating problem.. replaced the dash and all the plugs and whatnot, the thing started right up and no engine light.. all the lights work and windows etcetera, however..

with key off turning on the lights displays the turn signal arrows on (both of them, not flashing).. the side marker lights aren't lit, but the turn signals on the bumper are..

with the key on same thing.. if the lights aren't on, no arrows, when the lights are on both arrows are lit.. when you turn on the turn signal (either way), the proper arrows blinks, but the marker light blinks instead of the turn signal light (I think they're supposed to both blink alternating)..

there is one plug (male) that has no corresponging plug *anywhere* that I can find that is under the dash on the left of the steering column, 6 pins and fastened to a metal bracket. I played around with the voltmeter on the pins, blew the parking lights fuse once, and am now convinced that something goes in there..

does anyone know what or where?

lesson learned: don't take it all apart, leave it for a month, then expect things to go smoothly when you put it back together.

Reply to
keefemd
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Nobody sticking their necks out for this one, so I will try to be of assistence. I've yet to look at the schematics for this one, however, the circuitry involving the indicator lights are being either shorted to ground, or shorted voltage. Therfore, I'd be looking for an inadvertant connection, rather than connectors that are not connected to something. I've seen connectors on many vehicles that aren't connected (options that weren't purchased with the vehicle.) Hopefully it's accessible enough where u might try reseating the main connector to the dash, as it might be off just enough to make cross-connection. As far as the unplugged connector, how many wires are on it, and colors also? You might have already tried these things to no avail, but have noticed your entry go unresponded for some time. Hope it helps. Jim

Reply to
gobroncos

I'll take a guess too.

I would guess you have lost the ground for the running lights so they are stealing it through the signal light bases. Usually the running lights use a wire in the harness for ground and the signals use the fixture to the body for ground.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N>
Reply to
Mike Romain

If a circuit loses its ground, how could it be possible for them to light? With the switch off, it very well should be losing its ground (or losing its voltage, whatever the case may be.)

Reply to
gobroncos

The bulbs have two filaments in them. If the fixture loses the direct body ground for the signal/brakes, then the brake and signals will ground through the running light filament making the light dim because it is using two filaments.

If the running lights lose their wiring harness ground, they will try to steal it through the brake/signal light filaments so you get the arrows on the dash lighting up too as well as a dim signal/running filament light.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N>
Reply to
Mike Romain

The only way they could be stealing ground is thru a partial short: therefore, in essence, there is actually "no" loss of ground. I know Mike knows his stuff by his longevity with this group. Its my opinion that by resolving the dash indicator issue first, aside from the marker / signal lamp issue, one will resolve the problem altogether. Key-on engine off, light switch on, blinkers off, turn indicators on the dash should not be on. This being troulbleshot first for a partial short, I think will resolve the issue of the entire scenario. Loss of ground/ loss of connectivity is not the issue. This prob is difficult and while at first disagreeing with Mike, and after contemplating his answer, I dont think we disagree in electrical theory, but I think its easier to troubleshoot starting one prob at a time rather than say invloving markers,sidelights, turn signals and lights, alltogether. There's more than plenty to troulbleshoot with simply the lights on while signal indicators are not supposed to be lit. Jim

Reply to
gobroncos

The other bulb filaments act like the short.

What I posted happens all the time in Jeeps with their GM light circuit wiring.

I have one burned out running light and the arrow on the dash lit up I have to chase down in our Cherokee. I know mine is out by the light, his is a dash ground or headlight ground on wrong or not on likely.

Mike

gobr>

Reply to
Mike Romain

This is a fail safe used to notify the driver that a marker is out? This is very nice to know and must admit that I was not aware of it. You've encouraged me to obtain the schematics and check this further. If your listening Keef, check and recheck those connections under the dash! Thanx for the nice tidbit Mike, Regards, Jim

Reply to
gobroncos

My marker is out because the fixture is rotted. I believe something in the wiring or bulb needs to be broken or disconnected before the dash arrow comes on with the headlight switch.

In my specific case, I believe the ground for the running light has corroded away so it's stealing it's ground through the signal light filaments. The signal light has a filament at the bulb and in series another one in the dash arrow. That is why the arrow on the dash is lit up.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

I've got a 93 firebird with a dash arrow on. Now I know why! Very cool!Am still curious as to the physical nature of this wiring setup, and exactly how it "steals," the ground from the arrows when the bulb/or wiring on the marker become disabled. Draw me a picture Mike. Merry Christmas, Jim

Reply to
gobroncos

I can try to spit this out right....

Electricity will usually take the shortest or route of least resistance. It goes from the higher potential to the lower potential.

On the older GM's and Jeeps at least, the signal and brake light filament grounds through the bolts that hold the fixture on. In my case, 3- 1/4" bolts that show 0 ohms resistance to the body ground.

The running and marker lights have their own ground wire as most markers do not have a fixture ground through the bolts. A 16 or 18 ga. wire has 'some' resistance, way more than those 3 bolts.

Ok so far?

In Jeeps, the bolts that hold the fixtures on get rusty and fail to ground the fixture. The filament will then try to ground and not seeing the fixture ground it will feed from the bulb base back up through the running light filament and out to the marker light seeking the wire ground which it finds.

Then when you turn on the headlights and running lights, the brighter brake and signal will sense the 12 volts on the dimmer bulbs filament and use that 12 volts as a ground reference. It then lights up both filaments giving the dim signal light.

When the running light ground fails, it does the same thing and looks for another ground. It finds it through the signal filament and usually the dash light filament too so the dash arrow comes on dim.

I likely didn't get all that spit out correctly, but that is the general idea.

On your Firebird, I would be looking for a running or marker bulb that has failed first.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

I've had the dash tipped back again looking for stray plugs, but found nothing that matches up.. i've considered that it's for some option (daytime running lights or foglights) that I don't have, and that makes things a little more tricky..

i'll try checking all the plugs again, although I don't believe any are loose or incorrectly hooked up (all are different kinds).. the problem with the shorted ground doesn't sound like it applies to my situation (all lights are equally bright and the markers blink), but the turn signals don't.. also the situation applies equally to both sides (both arrows on, both markers blink but no running light, turn signals light for running but don't blink)..

it seems like it *must* be some wire(s) not connected properly so I'll give it another whirl... thanks all for the advice and I'll keep ya posted.

Michael

Reply to
keefemd

I am thinking you are missing a ground tag so the lights are grounding through alternate routes.

The headlight switch has a ground and the dash itself needs a ground.

Could the heater issue be because the body of the vehicle or the dash lost it's ground?

The main body ground on a GM is usually a wire mesh strap from the bell housing to the body. When this breaks or rots away strange light and heater issues happen.

I usually use a booster cable hooked up to the battery negative and use that clamped around to the body or dash panel if I suspect a bad ground.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N>
Reply to
Mike Romain

In conclusion to this thread, the problem was the bright side of both bulbs were blown (how, I have no idea, they worked prior to the work).

As it was explained to me, the turns signals draw the voltage off the dash arrow circuit, so when the bright side of the turn signal bulb is not lighting, the arrow on the dash does not go out...

In the end, no matter what you think the problem *might* be, and no matter how doubtful a bulb problem seems, ...check them *first*.. saves time eight out of nine..

thanks for everyone's help

Reply to
keefemd

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