Trailer Left Turn Signal/left brake light not working

bclmread · 07-03-2006, 06:29 PM

I haul a 27' travel trailer with my '05 LE.

Last weekend, someone at the campground we were visting told me the left brake light on my trailer was out. So I replaced the buld, and no change...still out. Its a dual filament bulb...the trailer running light works, but no left brake or left blinker. HMMM...

So we did some testing...we hooked my bro-in-law's 05 Titan up to my trailer...trailer works. We hooked my Titan up to his trailer, and same problem occurrs...no left blinker/left brake. So its the truck...

I run a Prodigy controller...could a loose wire in the Prodigy hookup cause a left side only brake/blinker light problem? I don't think there is anything about blinkers etc in those wires. I'm thinking there might be a problem in the connection from the Titan harness to the Prodigy, since on my way home tonight (from camping), my Prodigy was telling me I had no connection (as if there was no trailer plugged into the 7-pin), yet the running lights, and right blinking/brake lights worked on the travel trailer.

Good thing it was a short ride home...

Any ideas?

ablexus · 07-03-2006, 06:35 PM

Blown relay perhaps? Try swapping relays with your buddy and see if that does the same thing.

Andrew

**walleeme** · 07-03-2006, 06:40 PM

I would check the plug on the truck to see if a wire has been pulled out. Get a test light, and google search for the standard wiring setup for the RV plug and test the pins to see if they are doing their job at the plug. The other thing you can try is a relay swap up in the fusebox bin under the hood. Swap the left and right and see if the problem moves. If the problem moves, buy a new relay. I would actually try the relay swap first, unless you have reason to suspect the plug area of the truck for some reason.

Wally

Derwud · 07-03-2006, 07:29 PM

Check for a blown fuse first, if blown fuse check your trailer connectors and trailer wiring...

Prodigy has nothing to do with the brake lights...

Has your truck had the BCM harness recall?

bclmread · 07-04-2006, 06:35 AM

I agree...its not a controller issue. Ipulled the controller out, hooked the trailer up, and brake/blinker issue still exists. At least I fixed my trailer brakes by reconnecting the harness to the Prodigy.

I was under the hood this morning (scary thing for me to be under there).

I pulled the cover off the relay box and the fuse box. I checked any fuse that said "Tow" and they all look ok.

The relays are the squarish ones in the smaller box, right? Any trick to get them out? I pulled, and it wouldn't pop out, and I didn't want to break anything. I noticed that there was a trailer tow 1 and a trailer tow 2.

I have examined the 7 pin plug, and it all looks tight.

My truck has had the BCM recall performed at the dealer.

Sammy Sandbag · 07-04-2006, 07:30 AM

The tail lamps are controlled by trailer tow relay 1 (located in the Fuse and Relay Box.) Power is supplied to the tail lamp relay and a 10A fuse. The fuses and relay are located in the IPDM E/R (intelligent power distribution module engine room) which is just behind the relay box with the tow relays (next to the firewall.) The fuse is No. 36.

I would think you'd lose both tail lights if it were a fuse, since they follow the same circuit (in regards to just the tail lamps.) Now if it's just the turn signal and hazard (have you checked the hazards) then that it is controlled by the BCM and is seperate for left and right. Left is through BCM terminal 52, and power is supplied to trailer connector terminal 1 (your plug should have a schematic.) There is no fuse between the BCM and trailer, so nothing really you can check. BTW, the wire should be Green with a Black stripe.

Brake lamp power is supplied through a seperate terminal, based off of tge actual pedal.

So it's a bit confusing that both your left turn signal and brake light are not working. I could maybe see just the signal not working, but the left brake should work if the right does. Have you checked this with the running lights off (headlights completely off?)

Also, had you checked your lights following the BCM TSB? All this info is based on the '05 Titan prior to the fix, I have no idea what they might have done since then. Perhaps they messed up something during the fix.

Sammy Sandbag · 07-04-2006, 07:52 AM

BTW: Here's the BCM service campaign: http://www.nissanhelp.com/Ownership/.../NTB05-086.htm

bestatchess · 07-04-2006, 08:41 AM

Bcm Module Sub-harness Info

Sammy Sandbag · 07-04-2006, 09:03 AM

Quote:

Originally Posted by bestatchess

Bcm Module Sub-harness Info

Ah Ha! I knew it had to be something with that additional harness. From looking over the OE schematics there was no way for this to happen. Damn, and I tried to search for something like this. BAC you remain the search king.

Derwud · 07-04-2006, 09:34 AM

Thank you, you beat me to it...

Now, you need to figure out why those fuse(s) blew!

**walleeme** · 07-04-2006, 10:25 AM

Relays always look okay unless the have been catastrophically damaged. You have to test them to be sure they are working.

Pull the LH one and plug it into the RH plug and see if the problem goes to the other side of your trailer.

Wally

bclmread · 07-04-2006, 04:09 PM

I'll go looking for those new fuses right after I get home from work tomorrow!

I'll let you know what I find.

Thank you everyone for all the great insight! Titan Talk is the BEST!

bclmread · 07-04-2006, 04:40 PM

I couldn't wait until tomorrow...I took a flash light and went looking for those fuses, and of course, could not find them.

Can anyone give me some guidance as to where I might locate the new fuses (as referred to in bestachess reply)?

Do I need to pull dash panels off? I was looking above the throttle, and could see any fuses.

Thanks!

Sammy Sandbag · 07-04-2006, 06:32 PM

Quote:

Originally Posted by bclmread

Can anyone give me some guidance as to where I might locate the new fuses (as referred to in bestachess reply)?

Read the link I provided to the TSB. It shows pictures of where they are installed.

bestatchess · 07-04-2006, 09:04 PM

After I had the BCM harness done, I noticed that the turn signal seems to blink with a different sound/rate. I haven't hooked up any trailer yet, but my turn signals still work. I actually tested them right after I got it back from the dealer, because I thought that the different sound/rate might indicate something was amiss.