How to Trouble Shoot Wiring for TOAD

[Road-Chi]

Hope someone can help me get the wiring sorted to get our TOAD ready to go. Here is the situation:

Bought a Honda CRV that had been used as a tow vehicle on another motor home. It came with Blue Ox base plate and other equipment for towing, including a tow breaking system installed in the CRV. Our Motor Home has a female 6-pin receiver and the CRV has a female 6-pin receiver, and there is a wiring harness with male 6-pin plugs on each end. Yet, when the wiring harness is plugged into both the MH and CRV, the lights and brakes etc are messed up. When the harness is plugged in, there is a sound emitted from the CRV that may be the breaking system engaging; although that is speculation. Also, once the harness is plugged in, the right tail light on the MH turns on; whereas without the harness, all lights are off. I took a circuit tester and determined three active poles on the 6-pin on the MH: i) right turn signal / brakes, ii) left turn signal / brakes, and iii) running lights. Also, on the MH, with the key off and everything turned off, I could not get an active 12-volt signal from any of the poles in the 6-pin receiver on the MH. Does anyone have a recommended procedure for systematically matching up the wiring on the MH and CRV?

[Scottybdivin]

Originally Posted by Road-Chi

Hope someone can help me get the wiring sorted to get our TOAD ready to go. Here is the situation:

Bought a Honda CRV that had been used as a tow vehicle on another motor home. It came with Blue Ox base plate and other equipment for towing, including a tow breaking system installed in the CRV. Our Motor Home has a female 6-pin receiver and the CRV has a female 6-pin receiver, and there is a wiring harness with male 6-pin plugs on each end. Yet, when the wiring harness is plugged into both the MH and CRV, the lights and brakes etc are messed up. When the harness is plugged in, there is a sound emitted from the CRV that may be the breaking system engaging; although that is speculation. Also, once the harness is plugged in, the right tail light on the MH turns on; whereas without the harness, all lights are off. I took a circuit tester and determined three active poles on the 6-pin on the MH: i) right turn signal / brakes, ii) left turn signal / brakes, and iii) running lights. Also, on the MH, with the key off and everything turned off, I could not get an active 12-volt signal from any of the poles in the 6-pin receiver on the MH. Does anyone have a recommended procedure for systematically matching up the wiring on the MH and CRV?

Standard configuration for all trailers and tow vehicles. It almost sounds like one or the other has wires mixed up on the wrong prong.

[jrwitt]

The 12V signal will probably only work if the coach ignition key is turned on (or maybe on ACC). Also, some manufacturers don't connect the 12V wire to the connector. You may have to run a wire from the chassis battery to the connector to get the 12V. Be sure to put a fuse in the circuit.


To do a systematic check of the connectors and the cord between them, start with the cord unplugged and first check all the pins on the connector on the back of the MH. I would check the ground pin first to be sure it has continuity to the correct pin. If the ground is good, check the rest of the pins using the ground pin to ground you meter. You can find pics of the connectors on line. Google "RV 6-pin connector wiring" or something similar.

[56safari]

Get a circuit tester (looks like a pointed end screwdriver with a wire out the handle). They go for around $6-$7 at the local auto parts stores, Attach the alligator clip to the CRV's battery, then touch each pin. Check to see what lights on the CRV. If nothing lights, but the little light in the tester lights, you have found the ground pin. If you blow the little fuse in the tester, there is a power feed (12 volt) coming from the CRV. You can avoid the blown fuse by testing each pin to a ground before attaching to the battery. If the tester lights, you have power feed from the CRV,

When you have all the pins identified, take the plug apart and mark each wire's use based on the pin to which it is connected, remove the wires and reinstall on the pin that matches the pin you identified on the corresponding Motorhome plug for each use e.g left turn signal, right turn signal,etc.

Once you have finished the rewiring, plug into the motorhome and check that you get Left turn signal, etc on the CRV when you activate that item on the motorhome.

You can also make the corrections by plugging in the CRV and noting what activates on the CRV when you turn on lights, etc. on the motorhome. FOR example, you turn on the motorhome lights and the right tail light on the CRV lights. That means the pin on the CRV is wired for the right turn signal. When you have finished all the functions, you should know where each wire on the CRV plug needs to be to match the motorhome.

Both methods are harder to explain than do. Good luck!

[Road-Chi]

Thank you to everyone for your comments. Big help. It seems that the first thing to be done is to determine what each pole on the 6-pin receiver runs on the CRV. Does the following seem correct?
1. Determine the ground. How to do that?
2. Once the ground is found, go around and apply 12-volts to each of the other five (5) poles to observe what is activated on the CRV. Should the CRV's key be turned to ACC while this is being done?
How is the best way to apply the 12-volts to the poles? From the CRV's battery? From the positive terminal? Through or with the circuit tester?
Of course my strength is not electrical. Thus the simple questions above.

[56safari]

Road-chi,

I'm sending a private message with step by step instructions on the process.

[Road-Chi]

Did some testing on the wiring with a circuit tester today. Here is what was found when testing the coach's and toad's 6-pin male receivers.

On the coach: With the key turned to ACC, the 6 pin receiver shows: 1) no 12 volt, 2) right TS/Brake, 3) Left TS/Brake, and 4) running lights. Could not determine which prong was the ground. Method used was: connect alligator clip of tester to a screw into the chassis (to serve as ground); then got tester light on for Items 2 through 4 previously.

On Tow Car (i.e., the CRV): four of the prongs caused the circuit tester to light with the alligator clip connected to the positive pole of the CRV battery. Does this indicate four grounds, and if so, then what? Also, two prongs -- on the CRV -- seem to be 12 volt hot; one causes a motor sound (probably the brake control system being energized).

Tried to check the CRV's wiring by connecting the alligator clip to the positive pole of the CRV's battery, and then touching the tester to prongs to see what was illuminated. Got nothing. No turn signal lights, etc. Had the key to ACC during this testing.

Basically, I am stumped. Any thoughts on how to proceed?

[ChasA]

Road-Chi,
I think your coach has combined brake/turn signals and your CRV has separate brake and turn signals. If this is the case, you will need to install an adapter to convert the wiring in the CRV. Any auto parts store should have them.