Trailer Lights/Wiring Harness

[CJLUJAN]

This is my first post, so please bear with me.



I am posting this for a friend who has a 2003 ho CTD 2500 quad cab 4x4. When he plugs in his trailer light to the factory harness the left tail/turn light does not work. The fuse is not blown in the fuse box located in the engine compartment above the left fender well. As best as we can tell the wire is continuous all the way back from the fuse box to the plug.



Would appreciate any sugestions on where to look for the problem.

 

[dennmont]

Take a test light to the trailer plug, turn on left turn signal, test light should flash with left turn signal. make sure to ground the test light at rear of truck

 

[CJLUJAN]

Already di that and their is no current at the trailer plug.

 

[Bachant]

My truck did the same thing. Had to have the dealer flash the ecm to correct the problem. The ecm has an internal circut breaker. The reflash ups the amp from 15 to 20 on that circut. They did it for free, they said it was TSB.

 

[CJLUJAN]

Thank you. Do happen to have the TSB number? Would make it easier when he goes to the dealer.



Again thanks alot.

 

[Bob4x4]

There is a flash for the 06 trucks(tsb 08 021 06 ) to increase the amperage draw allowed,it does not apply to the earlier models. They use a slightly different design.



Bob

 

[LHeugel]

We have the same problem with our 2003. Did any of these posts help you? Did you get your problem solved? If so, what was wrong?

 

[jelag]

I don't think the 03 have the ECM control like mentioned above...

My 04, 04. 5 and 05 all have a separate fuse in the panel for the trailer system... I believe the ECM control didn't appear until the 06 or 07 model... .

So check for another fuse that controls the LT, RT, tail, etc... .

 

[Morsed]

and newer have a power distribution control unit that can blow, my part # is CMC 68005474AA price 458. 99 total install 719. 30.
The symptoms sound the same, no left turn and fuses intact... An internal post in the PDC seems to be too small for the amps and blows instead of the fuses. Mine was caused when the 4-wire plug corrodid and shorted out the tail and left turn lights... This is for the trailer plug only and does not affect the truck lights... .

Dave

 

[scottmcd]

Truck goes in Tuesday to the DEALER#@$%! to get the wiring checked. I am going to go ARMED with the the info from MORSED to help the "5 STAR IDIOTS" figure it out. I will post after I get it back.....



Scott

 

[Bob4x4]

Why do you feel the need to call strangers idiots ?



Bob

 

[ryecreek]

I have the same trouble from what i've read it's the power distrbution center ($450) mine i can hear a flasher/relay making a funny noise when left turn is on chased out wiring and thats where i ended up have not bought one yet though

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