I have a 2014. While hooking up our new camper I noticed the left brake/turn indicator light doesn't work. I tested the connector at the hitch and I have no power to that pin. Any ideas where to start and how to troubleshoot? I have check the fuses and swapped the relays for the trailer turn signals with no luck.
Trailer lighting issue
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Can anyone help? I cannot fix this issue. I have swapped out relays but that didn't help. I read the older trucks 2008 or so have additional fuses for the trailer wiring under the dash. Do the later years also have these? If so any idea where I can find them?
Can anyone help? I cannot seem to figure out this issue. I have tried swapping the relays but they work fine. I read that older models have addition fuses under the dash. Do the later model years also have these additional,fuses? If so any idea where exactly I can find them? I have no trailer left side brake or turn indicator. Any help would be greatly greatly appreciated.
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Did it ever work that you know of? Maybe there was a mispin at the factory? Hard to tell from the manual which contact is supposed to be at what location at the connectors but you could chase the wire colors if you had to. From what I can see in the maintenance manual (Haynes) the left signal and brake light are the same pins at the trailer disconnect. So it would make sense that you don't have either brake or signal indicator if you don't have power at the connector. I would check continuity from the right brake/signal pin at the trailer disconnect plug and the right trailer turn relay and I'd compare the pin that rings good on the relay socket to the one on the left and what should be the left pin at the trailer connector. Also check the ground at the relay to see if they have continuity to chassis ground. Can you hear the relay working when trailer is connected and left signaling? If the relay appears to be working then there is likely a wiring issue. You could back pin the relay when it is signaling and check voltage at what should be the green/black wire at the left trailer turn relay. Hopefully its not the body control module... Good luck and let us know what you find
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Dont know how accurate a Haynes manual is for these trucks, but it shows 1 fuse (fuse 60 15 amp) powering both left and right relays. If the schematic is correct, power shouldn't be an issue.
Edit, unless there is a fuse for the relay exciter that the manual doesn't show at/after the BCM....
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I posted that picture earlier too, and deleted it. The description says 04-05 only for the under the dash fuses...again, not sure how accurate these sources are, and its raining outside here in the coastal empire so I really don't wan't to check mine right now.There could also be 2 added fuses under the dash by the column.
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No luck. Still can't figure it out. I did not see any additional fuses under the dash. I swapped relays but they are both good. Still no power to the one pin (yellow wire I believe) Without a lift it's really hard to trace the wires. I also disconnected the trailer harness from the trailer socket to make sure the socket itself wasn't the issue. Where does the trailer harness meet the main harness any ideas? Any other connections I can check?
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I know this isn't a solution anyone wants to hear but I ended up taking mine to a dealer that I trust (they have been working with me since 1978 on all my Datsun/Nissans). They found that one of the wires in the harness had broken and shorted one of the fuses. Took a couple day for them to track the right cable and correct, cost around 250 for diagnostic and repair but I'm up and running without any issue. Also, I found a Nissan Tech/Service Manual online for free to download. I have to look up the link but found it through the NICO forums (link is NICO Club - Nissan Forums | Infiniti Forums). At least a start.
If you have access to a PS2 brake controller.... it has a display code for shorted (SH) wire connections...even if the trailer isn't connected. Without that in the display, I'd know I was chasing a broken yellow wire. With it, I'd look for a crush spot on the harness. Either way, you're investing time in piercing wires with the multi-meter to find the culprit.
Here are detailed instructions from the manufacturer:The first error code, SH, you are seeing on the Prodigy Brake Controller, means the brake wire sees a short circuit during idle condition. The second code, OL, indicates an overload condition during operation.
For the first code, SH, the most likely problem is a pinched wire or at some point the wire insulation has cracked or been worn to the point where the copper wire inside is making contact with the trailer frame or another metal part. To find the problem, you will need to start at the trailer connector, making sure it is not corroded, dirty, or damaged, then work your way back to the brake magnets, examining the wire as you go. The fix is to replace the damaged wire and/or clean off the connector.
The second code, OL, could be related to the first. A short between the brake output pin and the ground pin on the 7-Way could cause an overload. Cleaning the connector of any dirt or corrosion would be the first thing to try. If you still have the same problem, sever the connection of the blue wire at the back of the brake controller. Leave enough wire to reconnect the wire after testing.
Once the blue wire is severed, if the brake controller returns to normal function and the decimal point returns on the display, you know that the problem is on the blue wire somewhere between the controller and the connector at the rear of the vehicle. You may need to run a separate 10 gauge wire, # 10-1-1, to the trailer connector to bypass the problem, unless you can locate, isolate, and repair the bad spot in the wire.
Here are detailed instructions from the manufacturer:The first error code, SH, you are seeing on the Prodigy Brake Controller, means the brake wire sees a short circuit during idle condition. The second code, OL, indicates an overload condition during operation.
For the first code, SH, the most likely problem is a pinched wire or at some point the wire insulation has cracked or been worn to the point where the copper wire inside is making contact with the trailer frame or another metal part. To find the problem, you will need to start at the trailer connector, making sure it is not corroded, dirty, or damaged, then work your way back to the brake magnets, examining the wire as you go. The fix is to replace the damaged wire and/or clean off the connector.
The second code, OL, could be related to the first. A short between the brake output pin and the ground pin on the 7-Way could cause an overload. Cleaning the connector of any dirt or corrosion would be the first thing to try. If you still have the same problem, sever the connection of the blue wire at the back of the brake controller. Leave enough wire to reconnect the wire after testing.
Once the blue wire is severed, if the brake controller returns to normal function and the decimal point returns on the display, you know that the problem is on the blue wire somewhere between the controller and the connector at the rear of the vehicle. You may need to run a separate 10 gauge wire, # 10-1-1, to the trailer connector to bypass the problem, unless you can locate, isolate, and repair the bad spot in the wire.
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I understand you swapped the relays to make sure they were working, this tells you that the relays are good and the socket for the right side is good. Do you have power and grounds at the left relay itself? Does the corresponding contact/socket/pin at the left relay recepticle have continuity to the trailer plug (pin 7)?
I ended up going to the dealer. They offer 1 hour of free diagnostics before they charge. It's a bad connector someplace towards the front (guy at counter wasn't sure exactly) they found it in about 20 min. Gonna cost 130.00 for the part and the labor to fix.
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I bet they checked for power and grounds at the relay socket receptacle and used a half split bracketing techique to isolate the open wiring...it is difficult to do this kind of troubleshooting with substandard manuals and not knowing how the harnesses are routed. It can be done but is invasive and time consuming. Glad you got it all sorted out and the issue is resolved.
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