2nd Gen Non-Engine/Transmission Lighting problems. Bad ground?

[JPulliam]

For a while now my interior lights have been turning off and on randomly, so I replaced the headlight switch. On the way home tonight my headlights started going out. They turn on and off randomly now with the interior lights. Clearly the headlight switch is not the problem. #@$%! I am assuming I have a ground problem. I just don't know where to start looking. Anyone have any idea about where to start looking?

 

[Silver_Ram]

Check all battery connections (both + & -), follow the cables & wires from the negative terminals, check under the dash - there may be several. Was the connector for the headlight switch burnt or look like it got too hot?



Are you talking the main cab interior light or the map lights? Check the wiring & connections going to the light- may have a problem in the fixture. Have you added or installed any electrical parts recently?

 

[fest3er]

The interior lights (dome and map) have constant B+ applied. All they need to light is a ground on the 'bottom' side of the bulbs; ground is provided by the headlamp switch, the map light switches and the door jamb switches.

So,some clues: Do the door jamb switches work correctly? Or intermittently? Or not at all? The wire to a switch may have broken off, a switch could be 'out of adjustment', or a door hinge or latch could allow the door to move enough to activate its switch. Also, is the seatbelt warning light coming on when this happens? The answers should all yield clues.

It's possible that a ground wire running to any of the switches could have abraded its insulation, allowing it to ground the circuit in an undesired location.

If the switches all work properly, start finding places where the wiring could be both loose enough to 'bounce' as the truck is jostled and near a potential ground, then work my way to the harder-to-access places. Jiggle wiring harnesses in a way that would simulate their natural motion in a jouncy truck.

If you still find nothing, you may have to dismantle stuff and trace the actual wires.

 

[JPulliam]

The headlight switch wires are terminated individually with female spade connectors. It looks like the previous owner may have cut the plug end off and done this. However, the wires did not appear burnt. I am talking about the main cab interior lights, such as instrument lights. The headlights are doing it now, too. I have not recently added any electrical accessories. The door jamb switches work correctly, the seatbelt warning light is on constantly. I have a service manual on CD. Does it list all ground locations on the truck?

 

[fest3er]

Section 8W documents the wiring. It shows all circuits, connectors, grounds, splices, supplies, etc.

Is it correct to say that the headlights and interior lights turn *off* and *on* randomly, only happens when the head/parking lights are on? Or is it independent of headlight operation?

Looking at the SM (my '98 12V book), connector #1 on the headlight switch does have a ground that can turn the courtesy lights on. (Obviously, since the switch can do this).

Hmmm. Try snaking a length of electrical tape around the lugs on the switch, to separate all the lugs from each other. Remember, a connector serves two purposes: (1) to make it easy to connect/disconnect, and (2) to keep all the connections separate from each other. Your trouble *might* be that lugs/wires are intermittently making contact with each other, causing lights to go on and off by themselves, independently of the switch position.

 

[JPulliam]

Section 8W documents the wiring. It shows all circuits, connectors, grounds, splices, supplies, etc.

Is it correct to say that the headlights and interior lights turn *off* and *on* randomly, only happens when the head/parking lights are on? Or is it independent of headlight operation?

Correct. When the parking lights are on the interior lights randomly go on and off. When the headlights are on, the interior lights go on and off as wel as the headlights.

Hmmm. Try snaking a length of electrical tape around the lugs on the switch, to separate all the lugs from each other. Remember, a connector serves two purposes: (1) to make it easy to connect/disconnect, and (2) to keep all the connections separate from each other. Your trouble *might* be that lugs/wires are intermittently making contact with each other, causing lights to go on and off by themselves, independently of the switch position.

I will try this tomorrow evening.

 

[JPulliam]

No change with the tape. It must be a ground. I tried replacing or tightening the spade terminals to no avail.

 

[JPulliam]

I assume a ground because the problem has gone from the dash lights to the headlights. I am going to work on this more tomorrow night. My urn signals also work randomly. Could it be in the multifunction switch?

 

[fest3er]

You might be getting closer. Ensure the brake pedal switch is correctly adjusted. Examine the wiring going into the steering wheel, especially if you adjust the tilt wheel a lot.

For the MFS to be the problem, it would almost have to be a loose/abraded +12VDC wire/connector/rubbish bouncing against something going to the turn signals, HCMSL, headlights, et al, as the MFS sits between +12VDC and the devices being operated. I won't say it shouldn't affect parking lights, since Chrysler has been known to have weird circuits. ('69 Polara wagon: key off or out, turn on 4-ways and wipers, step on brake and the wipers would work through the flasher unit. )

If this yields no answers, you'll likely have to start unplugging connectors until the symptoms go away.

As a last resort, start the engine and wire the fuel shutoff open (so the engine keeps running), then turn the key off (but not locked) and see what happens. If the truck's lewd behavior continues, the problem lies somewhere in the B+ circuitry. If it stops, the problem lies somewhere in the ACC/RUN circuitry.

 

[2-ND TIME]

Lighting problems

By chance is this fed with a fuselink. IF so maybe bad? The multimeter will tell the answer. They are good for checking resistances.

 

[JPulliam]

The multifunction switch is not the problem. I switched it with a good one and the symptoms remain. Sometimes when the headlights go out I can wiggle the headlight switch wiring and the lights respond off and on. Other times it makes no difference what I wiggle. I checked the wiring to the multifunction switch up the column and found no worn or broken wires. I am pretty good with a multimeter if I know where to look and what to expect, but I cannot figure this thing out. What is the B+ circuitry? It does not matter if the key is on or off. Happens with the brights, too.

 

[2-ND TIME]

Lighting problems

If you can Isolate (remove one side to stop backfeed) a wire or terminal to ground put your meter there move it as you can to see if there is any fluctuations in the meter? If you replaced the switch and the lights still come off and on? Then switch is good? If you are able to pull off one side wire put you meter across the switch and move it watch that it varies smoothly? If sounds like you have wires in some terminal that are loose? You may want to have a long wire to go from terminal on the light its self to the cab area.



Good luck on it keep us posted.

 

[JPulliam]

Update: I put the old headlight switch in, and the headlights stay on now. The interior lights stay on, and the turn signals still work intermittently. I wonder if I traded one bad headlight switch for another. Any ideas?

 

[2-ND TIME]

Lighting problems

Use your multimeter to check the contacts and rehostat for smooth operation. This will tell you if the switch is good or not? Sorry don't know the pinout but play with it and write down what you find from point to point.

 

[JPulliam]

The rheostat operation would tell me if the headlight circuit is working correctly?

 

[JPulliam]

You might be getting closer. Ensure the brake pedal switch is correctly adjusted. Examine the wiring going into the steering wheel, especially if you adjust the tilt wheel a lot.

The wiring appears to be OK. No worn wires.

 

[fest3er]

It's looking like it might be closer to the headlight switch.

I had something else to try but just thought of something more probable. Remove the connector (or lugs) from the switch contacts. Check all the lugs and make sure they all will tightly grip the spades on the switch. If necessary, use a small needle nose plier and gently reduce the gaps until they're sure to make solid contact with the spades.

The 'usual suspects' haven't turned anything up. So it's time to take a deep breath and begin the systematic verification and exclusion process: start at the battery '+' post and work your way through to the battery's '-' post. *Something* will become evident.

A lot of this troubleshooting is second nature to me *when I am doing it myself*. Armchair troubleshooting doesn't fire all the associated neurons, so I don't think of everything sitting here. So:

• Ensure connector bodies are sound and mechanically lock into position.
• Verify that all spade and lug connectors make solid physical contact. Narrow the gaps on lugs as needed. They should require significant force to connect or disconnect.
• Ensure that the crimps connecting the lugs/spades to the wires are solid. You can solder them if needed. If they're iffy, old and tarnished, cut them off and crimp and solder on new lugs/spades.
• Trace the wires for a distance, feeling for breaks. A broken wire usually creates an obvious point of discontinuity in the smoothness of the insulation.
• Check all connections from the battery's positive post (B+), through the lights, through the ground/negative connections, and back to the battery's negative post. Check all switches and relays for proper operation.
• Get a general sense of how 'good' everything looks. If things are generally in good shape, you should easily spot the few things that are in poor shape and in need of repair.

I can almost guarantee that if you trace and jiggle everything in the circuit, you will see or feel something that's not right or you'll do something that replicates the problem. It's a PITA, but you'll learn a lot about the truck in the process. The SM for my '98 cost over $100, but it has been worth every penny; if you don't have a service manual for your truck, find one; print versions and CDs can be found on ebay.

 

[JPulliam]

Remove the connector (or lugs) from the switch contacts. Check all the lugs and make sure they all will tightly grip the spades on the switch. If necessary, use a small needle nose plier and gently reduce the gaps until they're sure to make solid contact with the spades.

I did this. All connectors now make very snug contact.

• Ensure connector bodies are sound and mechanically lock into position.
• Verify that all spade and lug connectors make solid physical contact. Narrow the gaps on lugs as needed. They should require significant force to connect or disconnect.
• Ensure that the crimps connecting the lugs/spades to the wires are solid. You can solder them if needed. If they're iffy, old and tarnished, cut them off and crimp and solder on new lugs/spades.
• Trace the wires for a distance, feeling for breaks. A broken wire usually creates an obvious point of discontinuity in the smoothness of the insulation.
• Check all connections from the battery's positive post (B+), through the lights, through the ground/negative connections, and back to the battery's negative post. Check all switches and relays for proper operation.
• Get a general sense of how 'good' everything looks. If things are generally in good shape, you should easily spot the few things that are in poor shape and in need of repair.

• Done.
• Done.
• Done. Replaced two connectors.
• I did this going back from the headlight switch and from the multifunction switch. No obvious breaks, scrapes, or worn wires.
• Check for continuity? OK. Is there a headlamp relay? I did not see one.

I can almost guarantee that if you trace and jiggle everything in the circuit, you will see or feel something that's not right or you'll do something that replicates the problem. It's a PITA, but you'll learn a lot about the truck in the process. The SM for my '98 cost over $100, but it has been worth every penny; if you don't have a service manual for your truck, find one; print versions and CDs can be found on ebay.

I have jiggled almost everything I can get my hands on. The headlight switch is the only thing that responded, and it did not do it consistently. I have a service manual for a 2001, but it lacks a little in the electrical department since it is for a different year.

 

[JPulliam]

I darn near pulled the driver's side of the dash apart to get the headlight switch wiring harness out. I found out that Dodge likes to run wiring harnesses across the sharp press panels that make up the steering member. Anyway, when I got the harness out I checked each wire for cuts. Only the solid green wire had a slit on it, and it did not look like the bare wire was exposed enough to short. I covered it in liquid electrical tape. Now, let's cover what has happened since the last time I posted. I bought a new multifunction switch and Borg Warner headlight switch. The headlight switch was installed Saturday night, and all the lights worked just fine. The interior lights went out again Thursday morning on the way to work. All the other lights worked fine. Tonight I was getting ready to go somewhere, and thought I would see if I could get the interior lights to work. I wiggled the headlight switch, and there was a spark between the metal on the headlight switch and the dash. Don't ask me how it sparked. I know the dash is plastic. Now, my running lights do not work. If I pull the headlight switch out halfway between off and the first click the parking lights and interior lights will come on. They go off in any other position. Did I fry my new switch with the green wire being shorted? Any more ideas? This makes me worried to drive at night again. Thanks!!!!!

 

[Missouri Mule]

The multi-switch operates the turn signals. The headlght switch should have nothing to do with them.

If the old headlight switch is working leave it in and concentrate on the turn signals.

Only thing the multi-switch has to do with the headlights is the highbeam.



The headlight switch was known to over heat but I thought they took care for the 98-98. 5 models maybe it was the 3rd gen they put relays in the system.