Posted 2010-10-15 4:51 PM (#125808) Subject: trailer or truck wiring -can't figure it out
Member
Posts: 5
Location: Plant City, Fl
When I have my truck lights on - Hit the brake, the truck pings and says check trailer wiring. The lights all work on the trailer - brakes and turn signals. It has been checked by a trailer company and there are no shorts? - It all started when I was driving without a left rear brake light - (but no truck pings or saying I needed to check my trailer wiring) So we checked it out and found that it was not grounded. Once grounded the light worked but then I started to get the pings and check trailer wiring. Also we replaced a tag light at the same time. We have also replaced the connector to the trailer and we have two truck connectors one in the bed of the truck and one on the bumper and it doesn't matter which one it is plugged into. Have had the lights checked and also the truck - no one can find out the problem - any ideas on how we can find it. We are going to be on the road for 22 hours next week and really hate to think we have to listen to that the whole trip. Help
Posted 2010-10-15 11:11 PM (#125818 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Expert
Posts: 1416 Location: sc
What year truck, trailer, and what brake controller? Do the brakes work? Usually when the controller says check brakes it is due to a poor ground. Was your new electrical cord on the trailer grounded well? Are your brakes grounded to the frame or do they have a dedicated ground wire?
Posted 2010-10-16 6:45 AM (#125822 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Regular
Posts: 87 Location: Williamsburg VA
When our truck has indicated a problem, it has been that a connector in the trailer plug is not making good contact with the truck plug. Check and make sure all contacts are clean and one contact has not pushed back into the plastic plug.
Posted 2010-10-16 6:50 AM (#125823 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Member
Posts: 5
Location: Plant City, Fl
The truck is a 2007 GMC 3500 Diesel DURAMAX/ALLISON trans. Trailer is a 2001 Exiss 3 horse trailer w/ living qtrs. The connection to the trailer we redid and made sure everything was secure and in order. It all started when we had no left rear light or brake light. Everything else except the tag light was working and NO "ck trailer wiring " from the truck. Then we took out the left back light on the trailer and found the wire that was grounded with a rivet had come loose. We put a screw in to ground the wire. Then the "Check trailer wiring " started only when the lights were on and we hit the brake. During the day when it is on auto we have no problem. Also we took the truck to the dealership and they just replaced the breaking box. We are driving to Tx in 4 days and can deal with the "ck trailer wiring" light but the ding, ding - everytime we hit the brakes will be annoying to say the least.
Posted 2010-10-16 1:36 PM (#125836 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Expert
Posts: 3853 Location: Vermont
The controller is indicating a problem with continuity. Pull the head on your plug (trailer) and check for loose connections (they can become loose over time). Check your wiring all the way back to the hubs, you could have snagged the wiring with road debris and pulled the wire from the clips (I hate these) used at the hubs. How many miles on the trailer brakes? How much wear? Have you pulled the drum for an inspection (easy to do)?
Posted 2010-10-16 2:02 PM (#125839 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Member
Posts: 5
Location: Plant City, Fl
We just put on a new plug on the trailer and were very careful to install it the same way as the old one- The trailer place also checked the plug on truck - which we have 2 and both did the same thing. The wiring from the front of the trailer is all we can get to - everything else is enclosed within the trailer. Is there a way to pull off each light on the trailer and check from there back to the back light with a meter to see if there is an exposed wire? - Otherwise we will have to have the trailer rewired and I'm sure that isn't any easy job since none of the wires are exposed. Also does this signal mean we have a bad ground? Any advice or thoughts on this are greatly appreciated.
Posted 2010-10-16 3:23 PM (#125846 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Expert
Posts: 3853 Location: Vermont
Do you have a friend who has a trailer that you can plug into and determine if the problem is in your truck? If you have the same problem with their trailer then it's in your truck...if NO PROBLEM...then its in your trailer...
Posted 2010-10-16 3:30 PM (#125847 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Expert
Posts: 3853 Location: Vermont
#PIT4366A: Check Trailer Wiring Message Displayed On DIC - keywords connector electric hydraulic ITBC IPC tow towing wire - (Mar 6, 2008)Subject: "Check Trailer Wiring" Message Displayed On DIC Models: 2007-2008 Chevrolet Silverado2007-2008 GMC Sierra With RPO JL1 This PI was superseded to update model years. Please discard PIT4366. The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.Condition/Concern:Some customers may experience an intermittent "Check Trailer Wiring" message in vehicles equipped with ITBC (Integrated Trailer Brake Controller) RPO JL1 and no DTC's stored. This message may be displayed each time the trailer's running lamps, turn signal lamps or brake lamps are turned on, especially if the trailer is equipped with a large number of lamps.This condition is most likely caused by insufficient trailer grounding and the trailer ground wiring will need to be repaired and/or upgraded. Recommendation/Instructions: To correct this condition, perform the following procedure:Inspect and clean the ground wire (normally white wire) connection on the trailer side of the 7-pin connector.• Make sure that the wires inside the trailer side connector are clean and securely fastened.• If an electrical junction box exists on the trailer, make sure the wires inside the junction box are clean and securely fastened.Once this procedure is complete, check to see if the condition has been corrected. If the condition still exists, perform the following procedure: 1. Remove the original trailer ground wire (normally white wire) from the trailer side of the 7-pin trailer connector. 2. Install a ring terminal (PN 12103512 or equivalent) to this wire and fasten the ring terminal to the metal or aluminum chassis of the trailer using a M6x1x20 self taping phosphate zinc coated screw (PN 11515925 or equivalent). • Pre-drill trailer chassis location with a 3/16" hole. • Make sure the trailer chassis location is clean of paint or coating material prior to installation. • Galvanic corrosion between dissimilar trailer and screw metals may require that this ground location be periodically cleaned. 3. Obtain a sufficient length of minimum 10 gauge (5.0 mm) white wire and fasten with ring (PN 12103512 or equivalent) terminal to the trailer chassis at the same location as the original ground wire. 4. Install and fasten the other end of the new ground wire into the trailer side of the 7-pin trailer connector. 5. Install conduit on the original and new trailer ground wires and secure the conduit to the existing trailer harness. Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Posted 2010-10-16 6:07 PM (#125850 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Expert
Posts: 1416 Location: sc
I'm still holding to the ground being the problem. Grab your jumper cables and a couple bungie cords, clamp one end to bare metal frame on the pickup and the other end to bare metal on the trailer.........go for a drive.
Posted 2010-10-16 7:39 PM (#125857 - in reply to #125847) Subject: RE: trailer or truck wiring -can't figure it out
Expert
Posts: 3853 Location: Vermont
Originally written by PaulChristenson on 2010-10-16 4:30 PM
#PIT4366A: Check Trailer Wiring Message Displayed On DIC - keywords connector electric hydraulic ITBC IPC tow towing wire - (Mar 6, 2008)Subject: "Check Trailer Wiring" Message Displayed On DIC Models: 2007-2008 Chevrolet Silverado2007-2008 GMC Sierra With RPO JL1 This PI was superseded to update model years. Please discard PIT4366. The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.Condition/Concern:Some customers may experience an intermittent "Check Trailer Wiring" message in vehicles equipped with ITBC (Integrated Trailer Brake Controller) RPO JL1 and no DTC's stored. This message may be displayed each time the trailer's running lamps, turn signal lamps or brake lamps are turned on, especially if the trailer is equipped with a large number of lamps.This condition is most likely caused by insufficient trailer grounding and the trailer ground wiring will need to be repaired and/or upgraded. Recommendation/Instructions: To correct this condition, perform the following procedure:Inspect and clean the ground wire (normally white wire) connection on the trailer side of the 7-pin connector.• Make sure that the wires inside the trailer side connector are clean and securely fastened.• If an electrical junction box exists on the trailer, make sure the wires inside the junction box are clean and securely fastened.Once this procedure is complete, check to see if the condition has been corrected. If the condition still exists, perform the following procedure: 1. Remove the original trailer ground wire (normally white wire) from the trailer side of the 7-pin trailer connector. 2. Install a ring terminal (PN 12103512 or equivalent) to this wire and fasten the ring terminal to the metal or aluminum chassis of the trailer using a M6x1x20 self taping phosphate zinc coated screw (PN 11515925 or equivalent). • Pre-drill trailer chassis location with a 3/16" hole. • Make sure the trailer chassis location is clean of paint or coating material prior to installation. • Galvanic corrosion between dissimilar trailer and screw metals may require that this ground location be periodically cleaned. 3. Obtain a sufficient length of minimum 10 gauge (5.0 mm) white wire and fasten with ring (PN 12103512 or equivalent) terminal to the trailer chassis at the same location as the original ground wire. 4. Install and fasten the other end of the new ground wire into the trailer side of the 7-pin trailer connector. 5. Install conduit on the original and new trailer ground wires and secure the conduit to the existing trailer harness. Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Since I can't highlight any lines...I'll take them out of the above message to be more obvious...This message may be displayed each time the trailer's running lamps, turn signal lamps or brake lamps are turned on, especially if the trailer is equipped with a large number of lamps.This condition is most likely caused by insufficient trailer grounding and the trailer ground wiring will need to be repaired and/or upgraded.
Posted 2010-10-16 9:28 PM (#125863 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Member
Posts: 5
Location: Plant City, Fl
We did plug our truck into another trailer and it is the trailer not the truck. So now we have to start looking at the trailer - We will try what you suggested. Thanks.
Posted 2010-10-17 2:47 PM (#125892 - in reply to #125808) Subject: RE: trailer or truck wiring -can't figure it out
Member
Posts: 5
Location: Plant City, Fl
We are making a little headway - It doesn't ping now when we hit the brakes just the turn signals. Hopefully we will have it working correctly before we leave on Wed. We thought it was all working and rode about 3 miles - Then the turn signals started again but not the brakes- Hope when we take the connector box off in the back that is where our problem lies. I really appreciate everyone's help on this matter because it had the trailer place stumped and the dealership too.
trailer or truck wiring -can't figure it out
