I noticed recently my brake and turn signals are'nt working on my trailer, I checked for power at the 7 pin connector and have nothing. There is a 40 amp Maxi fuse in the engine compartment fuse box that is listed as controlling these exact items however it appeared fine, I replaced it anyway and still have nothing. Could it be a bad connection at the box?
Any suggestions will be much appreciated!
Nothin' worse than a lame ticket on the way back from fishin'

 

Hi CDe

You said no power to the 7pin plug. If your getting nothing, are all the fuses ok? does your 97 have a fuse box under the dash (drivers side), if so, check there to see if theres a fuse blown. Also check in the eng.compartment fuse box for a bad relay, ( 12V charge to trailer battery). Kinda trial and error but, look at the fuse diag. for your truck if you have the manual. So, if all fuses for the 7pin are ok then.....

Take a close look at the wiring harness under bed, go forward from the rear 7pin and see if its connected to another harness, if so, take a voltage/test light reading at that harness, if its still dead, then you know its forward, (between there and fuse box)
Bad fuse, bad wire, but i suspect a blown fuse. Look carefully under hood to see if theres more than one fuse box. I only mention that because someone here once said they found another fuse box under the hood, besides the main distribution.
My 99SC has 1 under hood and 1 under dash, thats all.

Hope that helps. Good luck. OT

 

Check fuse number 23 in the fuse box under the hood. It is a 10A. On my 99 it controls trailer turn signals and a few other things.

 

I have a '97 xl with the same issue. This is the second time this has occurred in the almost 5 years I have had this truck. The first time the truck was almost new, so I took it in to a dealer, they fixed it in a short time. As I recall they indicated that it was a relay.

this time I don’t want to spend the cash the Dealer is askin just to replace a relay again (if that is the problem)

I too have checked the fuses and found nothing. good luck and please let me know if you get a "fix"

 

I think- as I have not tested my lights- that there is an easy fix. I looked under my hood again, and was excited to find another fuse box. A small single row mini fuse block next to the large under hood fuse block. This is not noted or pictured in my 97 manual. but it did have a burnt out mini 20amp fuse.

try this - it was the fuse in the #2 position i believe.

 

Hi Thu Thanks for the input.

So there is another fuse box. Glad you found it.

You mayhave already figured it out but.....

On the relay, you just take it in and out just like a regular fuse. On the 99Sc there are two relays as i recall. One for the fuel pump, the other has to do with juice going to trailer.

I overlooked a intermittant fuse. I just looked at it and it looked ok. Drove me crazy till i finally did a elect. test on each suspected bad fuse. Over looked the slightly cracked element. Dummy me.

As i recall on the relays. If you turn ign.key on, then unplug the relay and plug back in, should here a clicking noise indicating relay working. Of course thats just one check. If in doubt, just get another one. They arent real expensive. Find a emptly slot in fuse box and put it there. I put a dot of whit paint on mine, so i could spot it easy.

Hi CDe ...anything posted here help????

Good luck. OT

 

I think- as I have not tested my lights- that there is an easy fix. I looked under my hood again, and was excited to find another fuse box. A small single row mini fuse block next to the large under hood fuse block. This is not noted or pictured in my 97 manual. but it did have a burnt out mini 20amp fuse.

try this - it was the fuse in the #2 position i believe.

 

Thanks for all the input guys!
All I need is the time to check all these leads out. Maybe this evening, I'm hoping to get the boat out this weekend. I need to get some more fishing in before the season ends!
I'll post what I find out.
Again thanks for all the help!

 

Hi CDe

Sure hope so. Seen a few accordian shaped boats & trailers.

Musta been towing at night with no running lights.

Good luck....OT