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dale farley
12-29-2016, 09:40 AM
I am trying to wire my PT Cruiser to tow behind the bus. The connector shown below with two wires is the turn signal. The one with three wires is the tail and stop light. I thought I could just connect 12v to the left or right turn signal and it would work, but it doesn't. I have tried every possible configuration, and ANY TIME I connect one of my turn signals, they both flash. There is no short between my wires. To make the turn signals work, I have to also connect a ground to one of the wires on the tail light. I have same/similar problems with my Honda CRV.

For simplicity, I am using a source to connect 12v and ground to the 4 wire flat connector that I have connected to the rear lights on the tow vehicle. Nothing seems to work right. I can find connector kits to install on on the CRV to pull a trailer, but that is not what I am trying to accomplish. Are all my problems caused by the lack of diodes in the circuit? I can find no information on wiring a vehicle to be towed. The bus has a tow module on it, but neither vehicle works right when hooked to the bus. I am missing something!!!

Pete
12-29-2016, 01:26 PM
Dale, wish I could offer advice on using the tow vehicles wiring. I have all ways made a wiring harness and drill a hole in the stop/turn housing to insert a bulb holder, and have an entirely seperate harness. I have always had to run the harness along the frame of the tow car with zip ties, eliminating the need for diodes, fuses, ect.

travelite
12-29-2016, 02:20 PM
Dale,

Google TIPM, Totally Integrated Power Unit. I'm not familiar with it but it looks like if you mess up the TIPM it'll set you back $900.00. I think diodes will solve your problem. The diodes will allow you to run a separate harness complete with power and ground to both taillights and turn signals while isolating your bus's harness from the car's harness and vice versa. I use the dual Roadmaster (https://www.amazon.com/s/?ie=UTF8&keywords=roadmaster+diodes&tag=googhydr-20&index=aps&hvadid=153723626138&hvpos=1t1&hvnetw=g&hvrand=14719494410793294447&hvpone=&hvptwo=&hvqmt=e&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9010330&hvtargid=kwd-88752882689&ref=pd_sl_5qmpp9ow4u_e) diodes. They're available at any Camping world. Each filament needs two diodes. One to isolate the bus while the car drives the load, and one to isolate the car while the bus drives the load.

Gil_J
12-29-2016, 03:44 PM
Dale,

The trailer connector on the car won't work. The reason is that the 4 wire trailer plug does not support the independent brake and turn signals your car has. Why not just wire directly to the vehicle's lights from the front tow connector? You can probably find all of the wires you need to tap under the driver's side dash. You will need a 2 to 3 wire converter in the car, like this one (Click Here) (https://www.etrailer.com/Accessories-and-Parts/Curt/C56196.html), to convert the combined brake and turn signals coming from your coach to the independent lights your car has. You may or may not need blocking diodes. They can't hurt, so I would install them.