2003 2500 trailer brake/signal lights not working

[Harrismeh9]

The trailer running lights work fine. I plugged the left brake light wire into the running light connection and it came on. I did the same with the right. All the lights work on the truck. I check the fuses and noticed the electric brake fuse was burned out so I replaced it but still don't have trailer brake/signal lights. There are a number of fuses associated with the trailer lights and I checked them all. Is there anything inside the cab, especially near the connector for the electric brakes that is fused or can be burned out?

Thanks,

 

[jelag]

The left and right turn signal have separate fuses in the panel as well as their own relays... . This is separate to the circuit for the turn and stop lights on the truck... You need to check all of these circuits in the fuse panel. .

There is nothing in the cab that effects the turn or stop lights on the trailer connector...

 

[Harrismeh9]

checked all fuses... relays?

I have checked ALL the fuses in the fuse box under the hood. I didn't see any associated relays though. I will double check for relays in the fuse box though. Thanks,

 

[Harrismeh9]

Trailer brake lights not working

Well I made my trip to Salt Lake and back with no brakes/turn lights on the trailer. The trailer was small enough that I got by with just the truck lights. I have rechecked everything and all looks okay. I did also find that the chmsl (sp??) was not working either. I have a topper and the high brake light used to work. Checked the connection (actually disassembled connection) but still not working. I check the output with my meter and no voltage on any of the brake light connectors. Any more ideas out there?
Thanks.

 

[Harrismeh9]

Replaced the fuse for the topper chmsl and now that works fine. Rechecked ALL the fuses for continuity and all ok. Put the voltmeter on the trailer left brake/turn fuse with the turn signal on. Voltmeter showed pulse every time the signal light blinked on the truck. Where are the relays for the trailer brake/turn signals?

 

[Bachant]

I had the same problem on my 06.

There was a circut breaker in the ecu that needed to be reset. Done by the dealer only with a special "tool". There also was a tsb about it. The circut was set for 15a and needs to be reset to 20a.

This is what I was told by the dealer when I had it done. I didn't make sence to me but it has worked great for the last 110,000 miles so I won't complane.

 

[rbattelle]

Put the voltmeter on the trailer left brake/turn fuse with the turn signal on. Voltmeter showed pulse every time the signal light blinked on the truck. Where are the relays for the trailer brake/turn signals?

So the wire to the trailer is carrying the proper voltage to actuate the lights? If so, then your problem is with the trailer, not the truck.



Bachant - there is no such 15A internal ECM breaker on 2003 trucks (as far as I know). Electrical system is completely different between 2003 and 2005-up.



Ryan

 

[Harrismeh9]

I was checking the voltage at the fuse not at the trailer connection. Nothing gets to the trailer connection. I hooked up the trailer to my suburban and all lights work there. Now I am using a trailer light monitor - the one with the leds on it showing pwoer to the various circuits - no power to the brake/turn signals. This is a 2004 (not 4. 5) 2500 truck.

 

[RDyson]

I don't have a brake controller, but had the same trailer blinker/brakelight problem. I had no brake lights or blinkers. Turns out it was the trailer turnsignal fuses in the fuse panel. Both were burned out. The first time I checked the fuse panel, I found the truck turnsignal fuses and they were good. I was not aware that there was a seperate set of fuses for the trailer. Once I got them changed, all is well.



Randy