2nd Gen Non-Engine/Transmission parking light nightmare

[MontgomeryB]

1995 3500 4wd dually w/mason body

I've read all the threads and tried everything to my ability. I still can't get to bottom of the problem. This truck is an electrical nightmare. I've replaced the ground strap, wire to fuel pump & solenoid taillights 2 headlight switches clearance light harnesses in the past year and I've owned the truck less than 2 years.

PROBLEM: Again the parking lamp fuse blows immediately when I was plowing:

Her's what I've so far:



1. Unplug plow=blown fuse (continued to plow with only truck headlights & transmission goes another story for another day)

2. Unplug harness for rear of truck=blown fuse

3. Unplug front parking lights & remove bulbs=blown fuse (didn't do clearance lights)

4. Check all wires(can't see all parts of wires) & relay box for corrosion to the best of my ability=blown fuse

5. Replace headlight switch again (#3)=park lamp works for 20 min then blows fuses immediately

6. Replace black/yellow wire to relay & relay next to headlight switch= blown fuse



As of now I don't know what else to do, I don't now how to read the electrical diagrams or how to use a multi-meter

And of course it is

going to snow in less than 12 hours and I need the truck for a 3 day business trip

Any help would be great thank you for your time :{ :{

 

[McLaughlin]

Not sure how much help this will be but looking at my 97 service manual, the Parking lights, fog light relay #1, radio(light?), overhead cluster(park lamp switch output), clearance lights, overdrive switch (lamp?), fog lamp relay #2, and fog lamp switch are all tied in some way to the parking light fuse. Since you don't have clearance lights, they wouldn't be a factor unless the wires are normally installed to support them even if the truck doesn't have them installed. Since you aren't familiar with a multimeter, it is going to be a bit more difficult for you. Do you have fog lights? If so, I'd pull the relays to see if that would cure the problem. Might want to look where they would normally be installed to make sure nothing is shorting the relay pins out. If you don't then your may be a short by an unused wire. I think the manufacturers use a common cable sometimes and so you may voltage running to a point where you wouldn't normally expect.

 

[MontgomeryB]

Thanks for the reply. I don't have fog lights and there are unused plugs hanging but not touching anything. Can a Multimeter check for shorts? Also I;m not sure where those relays are? I did find 2 small black boxes that 4 wires hook up in the front of the truck by the headlights, not sure what they are.

 

[McLaughlin]

The relays are located at the power distribution center(PDC). The PC is located on the front drivers side fender of my truck. The fog relays are the sixth and seventh relays on the right hand side (starting closest to the fender).



Yes a multimeter can check for shorts. Depending on the multimeter, the switch for shorts is usually identified by an "omega" symbol. Also, depending on the multimeter, it may have a audible tone when it detects a short. You can tell by touching the two probes together to see if you hear a tone. Otherwise you have to look at the meter to tell if a short exists. One caution is to have the power removed from the circuit when using the ohm function of the multimeter. Not sure what the small boxes are you mentioed.



I also found another note in the book:



The headlamp switch has three postions: OFF, PARK (parking lights) and ON, plus a dimmer switch. When the headlamp switch is in the PARK or ON position, the switch connect F33 to circuit L7 from the headlamp swithc, circuit L7 branches to power the front parking lamps and the rear tail lamps, roof identification lamps, fender lamps and rear license plate lamps. Circuit Z1 provides for a ground for the parking lamps. Ground for the roof clearance and identification lamps is supplied on circuit Z4.



I'm still trying to figure out where F33, L7, Z1, and Z4 are located in the manual.

 

[McLaughlin]

I should have asked earlier but which fuse is actually blowing? The one in the PDC or one of them in the fuse block?

 

[MontgomeryB]

The 15a fuse inside the cab. The one thing that very puzzles me is the parking lights worked for 20 min. or so and now its back to normal. Also if the switch went again is it still possible to locate the problem. Also who makes a good multimeter especially with that tone assistance. I read your installation with that summit harness. Is that the harness with the relays and could helpm solve my problem. Is there a way to check relays-good or bad? Thanks for your help.

 

[MontgomeryB]

I looked @ the PDC and I'm not sure which relay they are. Theres the 6 black boxes then the 3 buse fuses and the square 20a-50a fuses and all appear good. Obviously I can't see inside the black boxes so I'm guess. Is that manual a Dodge Tech manual? I have the one from Haynes for dodge pick-ups '94 - 01', are these alright or something like you own better.

 

[McLaughlin]

The 15a fuse inside the cab. The one thing that very puzzles me is the parking lights worked for 20 min. or so and now its back to normal. Also if the switch went again is it still possible to locate the problem. Also who makes a good multimeter especially with that tone assistance. I read your installation with that summit harness. Is that the harness with the relays and could helpm solve my problem. Is there a way to check relays-good or bad? Thanks for your help.

I just checked my manual again. It shows the 15A fuse(fuse 18 in the fuse block) you mentioned so our wiring seems similar. If the switch went again, it may be the problem. If you get/borrow a multimeter, you should be able to pull the fuse and check side away from the battery(side without power at the fuse block) to see if you have a "short" to ground. If you have a short or low resistance (less than a ohm) it indicates you have a problem further into the circuit. You could also pull fuse 13 (identified as ILLUM, a five amp) and see if the 15A fuse continues to blow. If it doesn't then you may have excessive current drawn from though the 5A circuit(I wouldn't think so since the 5A fuse should blow if the problem was there. ) If it does it indicates your problem is in the wiring supplying power to the parking light circuits or the fog lamp relays(which you shouldn't have) or the identification light wiring (which you also should have) or/overhead console.



Regarding the multimeter, most electronic stores or hardware stores will have one (Radio Shack, Home Depot, Lowes). You shouldn't have to pay more then $30 for a pretty good meter. Probably your best bet would be a digital "auto ranging" meter almost all of them have the audio tone (you can tell by a little speaker by the switch position. I've included a couple of pictures of volt meters I have. The first is a multimeter I picked up at Radio Shack for about $25. About the only thing I don't like about it is the test leads aren't very long and can't be removed/replaced. The other I've had for longer and is a bit bigger. Only problem with the bigger one is the knob came loose.



Regarding the summit wiring harness, unless you have had a series of light switch failure then it shouldn't correct your problem. If your light switch has been failing then it might. The summit wiring harness takes the majority of the headlight current load off the switch so it helps extend the life of the light switch by reducing the current and heat the switch has to handle.



Checking relays is fairly simple. Most relays show which connections should be open and which should be shorted. You can check these with an multimeter using the resistance position. Somethimes the contacts in the relay will "stick together" and that could cause excessive currents. So you have to check the relays "make" and "break" the connections as they are supposed to. The only other thing you need to check is if they switch when 12 volts is applied. Usually you can hear them switch. By monitoring the contacts as they switch you can tell if it is switching or not(may have to check for the presence/absence of voltage vice resistance).



I can try and come up with some copies of the diagrams if it will help.

 

[McLaughlin]

I looked @ the PDC and I'm not sure which relay they are. Theres the 6 black boxes then the 3 buse fuses and the square 20a-50a fuses and all appear good. Obviously I can't see inside the black boxes so I'm guess. Is that manual a Dodge Tech manual? I have the one from Haynes for dodge pick-ups '94 - 01', are these alright or something like you own better.

I included a picture of the PDC which has labels. I'm using a 97 Dodge Service Manual. I've used Haynes and Chilton before. I perfer Chilton but found that sometimes Haynes has information that isn't in Chilton and sometimes Chilton has info that isn't in Haynes. Neither does that well on electrical wiring. They are OK until you run into a tough problem or electrical problem like you've gotten into. If you have a pretty good idea what you need, I can probably extract it from the manual but sometimes the file sizes get pretty big. Some of the scans I tried were 11meg but I got them reduced to 1 meg pretty easily without loosing much resolution. The shop manual is by far the best reference I've found, even better then a soft copy on CD I purchased (the softcopy is incomplete). The service manuals are pretty expensive, I purchased mine on Ebay for $20(took months) but that seemed a fluke most were running $60 to $70 even on Ebay.

 

[JoshPeters]

If you have an aftermarket radio installed. Pull it and check the wiring. I've seen where the Illumination wire doesn't get connected..... and shorts to the metal dash support.



Also... do a search for parking lights. I believe HoleshotHoleset had a similar issue, he found the wiring chaffed through..... I believe it was under the ABS unit!



Josh

 

[MontgomeryB]

I appreciate all the information and time. I had a friend who is in the parts business and knows somebody @ a five star Dodge dealer. He dug deep and found my truck had the switch recall done in 2000, four years before I purchased the truck. After further investigation it seems the recall was performed incorrectly. That makes 4 switches in this truck. I'm not sure how it could be done incorrectly but, it seems like he's on to something. The sevice manager(friend of friend) has offered to look @ my truck and fix the recall correctly @ the cost to Dodge. I am going to try all the things you suggested and purchase a multimeter. If I haven't figured out the problem then off to the dealer. I hate to bring it anywhere to be fixed but, if its on their dime that's okay with me.

Lastly, I'm new to this site. How do you go about posting pictures with the threads.

 

[MontgomeryB]

Josh



I read that post and did check all those connections, all okay. I also have the stock radio in the truck. This thing is ridiculous and quickly becoming a money pit. Thanks for your help/



Brian

 

[MontgomeryB]

McLaughlin



One last thing, my PDC doesn't resemble the one shown in your thread its L- shaped w/ 6 relays on the truck. Unless this is just how they list it in the manual.



Brian

 

[JoshPeters]

Here's some solid ways to check your system out.



Matt (HoleshotHolset) Had some similar issues... . the thread is a good read.

http://www.tdr1.com/forums/showthread.php?t=112170&highlight=parking+lights



Good luck!

Josh

 

[tp0d]

I had exactly the same problem. Running lights would blow a fuse for no reason.



Traced it to the drivers intercooler outlet, theres a wire that feeds the passenger mark light/turn signal that was pinched between the intercooler and the metal fender. Would only pinch at certain times, the insulation was completely worn off. Would still blow a fuse even with the bulb out. . real bugger



Check both sides of the intercooler, inlet and outlet.



good luck



-j

 

[MontgomeryB]

Light problem still there after one day at the dealer even with the recall done correctly with the pig-tail added to the harness. They are no better off than I was when I brought it there. They now said that the dash needs to come apart and who knows what else. I'll keep everybody posted because I hope my misery can save somebody this same crap I'm enduring. #@$%!



Brian