Cornering Lamp Fuse Blows, Lose Headlights

[Corey Raub]

If somebody can point me in the right direction towards a fix on my car, I would be eternally grateful. I bought a 2003 Mercury Marauder a few months ago, and ever since I have had it, I have had a problem with the cornering lamp/hi beam fuse SOMETIMES blowing when I use my left turn signal. When the fuse blows, my headlights go out. The strange part is that this does not happen all the time, and it only seems to happen at night. I mean, when I use my headlights during the day, and use my left turn signal, the fuse will not blow.

When the fuse for the cornering lamp blows, should it affect the headlamps? I see there are 2 separate fuses for the right and left headlamps. I'm wondering if maybe my car is wired wrong, and if maybe this is the problem right here.

In an attempt to fix the problem myself I have done the following things to the car:

I have replaced all the exterior bulbs in the car.

I have replaced the multi-function switch.

I have replaced the headlight switch in the dash with a used one from ebay.

I have replaced the lighting control module with a "tested good" one from ebay.

I currently am having the left front fender replaced due to rust at a body shop, and while it is there, the shop is trying to help me diagnose my electrical issue. He said so far he has looked at the wiring at the front of the car with the fender removed, and he can find nothing wrong there.

Does anybody have any ideas on what to do next?

I can't tell you how much I have learned from this forum so far. Thanks to this forum, I was able to replace the blend door actuator (I still can't believe I did it myself), replace the 'O' rings in the control unit for the HVAC system, and I was able to successfully burp my cooling system after I had to replace a heater hose.

Thanks in advance for your time and help.

Corey

[fastblackmerc]

If somebody can point me in the right direction towards a fix on my car, I would be eternally grateful. I bought a 2003 Mercury Marauder a few months ago, and ever since I have had it, I have had a problem with the cornering lamp/hi beam fuse SOMETIMES blowing when I use my left turn signal. When the fuse blows, my headlights go out. The strange part is that this does not happen all the time, and it only seems to happen at night. I mean, when I use my headlights during the day, and use my left turn signal, the fuse will not blow.

When the fuse for the cornering lamp blows, should it affect the headlamps? I see there are 2 separate fuses for the right and left headlamps. I'm wondering if maybe my car is wired wrong, and if maybe this is the problem right here.

In an attempt to fix the problem myself I have done the following things to the car:

I have replaced all the exterior bulbs in the car.

I have replaced the multi-function switch.

I have replaced the headlight switch in the dash with a used one from ebay.

I have replaced the lighting control module with a "tested good" one from ebay.

I currently am having the left front fender replaced due to rust at a body shop, and while it is there, the shop is trying to help me diagnose my electrical issue. He said so far he has looked at the wiring at the front of the car with the fender removed, and he can find nothing wrong there.

Does anybody have any ideas on what to do next?

I can't tell you how much I have learned from this forum so far. Thanks to this forum, I was able to replace the blend door actuator (I still can't believe I did it myself), replace the 'O' rings in the control unit for the HVAC system, and I was able to successfully burp my cooling system after I had to replace a heater hose.

Thanks in advance for your time and help.

Corey

All those things you replaced won't fix the problem... as you found out.

This is what I'd do (one at a time):


Make sure the #27 fuse is 25A in the passenger compartment fuse panel.

Make sure the #21 fuse is 15A in the passenger compartment fuse panel.

Make sure the #113 fuse is 50A in the power distribution box (under the hood, behind the battery). I'd swap it with #112 and make sure the contacts are clean.

Remove the cornering bulb and see if the problem occurs.

Unplug the left headlight and see if the problem occurs.

Check the wiring harness at the left front corner of the car around the headlight and underneath the fender. This is a know problem area for the harness being chaffed.


Let us know what you find. You can PM me if you want.

[fastblackmerc]

Couple of questions:

Did the lo beams work when you got the car?

Is there any wiring that looks out of place under the dash or under the hood?

[Corey Raub]

fastblackmerc,

Thank you for replying so quickly. I feel honored to be communicating with you. I am somewhat nervous as I type this because I know you are well-respected on this forum. To answer your questions, 1. Yes, the car had the problem when I bought it. The previous buyer told me about it, but he didn't know what caused it. 2. I don't see any wiring that looks out of place under the dash or the hood.

When I tried to look at the wires (alot of wires) located in the left front fender, I found that the plastic loom seemed to have been 'opened up' and there was water laying in the loom with the wires. My body man said he looked at the wires in this area when he had the fender off and he could find nothing wrong.

Because the car is with my body man right now, and not at my house, I will call the shop on my lunch hour (11 am in PA) and ask him to try the things you suggested.

I will post what we find. Thank you very much!

[fastblackmerc]

fastblackmerc,

Thank you for replying so quickly. I feel honored to be communicating with you. I am somewhat nervous as I type this because I know you are well-respected on this forum. To answer your questions, 1. Yes, the car had the problem when I bought it. The previous buyer told me about it, but he didn't know what caused it. 2. I don't see any wiring that looks out of place under the dash or the hood.

When I tried to look at the wires (alot of wires) located in the left front fender, I found that the plastic loom seemed to have been 'opened up' and there was water laying in the loom with the wires. My body man said he looked at the wires in this area when he had the fender off and he could find nothing wrong.

Because the car is with my body man right now, and not at my house, I will call the shop on my lunch hour (11 am in PA) and ask him to try the things you suggested.

I will post what we find. Thank you very much!

I bet if they took a good look at that harness they'd find some bare or pinched wires. Check any connectors in the are for any corrosion, etc.

I know a few members have had issues with a corroded ground wire going to the foglight on the left side.

[Corey Raub]

fastblackmerc,

I have nothing to report at this time. I emailed ALL of the information you gave me to my bodyman so that he can try to remedy the problem. Unfortunately, I don't have the car at my disposal so that I can try your suggestions. As soon as I have anything to report, I will. Thanks again.

Corey