I have a weekend trip planned for the end of the month and my rear locker is still not functioning properly. I printed a few threads from the Mud forum here and spent some time under my vehicle over the weekend trying to diagnose the issue. It seems I am not getting +12V at the rear plug to actuate the motor. I get -12V when the locker switch is turned off but never get the +12V signal when the switch is originally engaged. While sitting in the cab I hear the relay at the passenger floor area make a single short click when the locker switch is turned for the rear locker. When the switch is tuned for the front there are two noticeable clicks from the relay. Tonight I plan on taking a 9V battery and verifying that the rear motor will engage as I have not done that yet. It seems to me that there is a relay problem or wiring issue but isolating the problem has been difficult to pinpoint. If I am not mistaken the same set of wires provides the +12V and -12V to the rear actuator so it does not seem like a broken wire back to the actuator since I get the -12V signal. I am at a loss as to how to check out the relay for proper function or how to get a new relay since I do not believe they are an available part anymore. Any help on the troubleshooting or relay replacement would be greatly appreciated. Also any other suggestions on troubleshooting would be helpful if I am totally going in the wrong direction. Thanks.
Rear Locker.....Again (1 Viewer)
- Thread starter extremesolo
- Start date
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Do you have your CDL switch engaged and locked when doing this?
The F/R lockers will not engage until it sees the CDL is locked.
The F/R lockers will not engage until it sees the CDL is locked.
- Thread starter
- #3
Yes, CDL is engaged. I should have stated that earlier.
I had exactly the same issue and spent a lot of time trying to track down the problem, I even took the ecu to an expert I met on these boards for diagnosis. In the end the problem was the actuator itself was shot, rust and corrosion. You could pull it off and apply power to it, see if it's working.
- Thread starter
- #5
I have a new actuator on the way, I just want to be able to verify it is not an electrical (relay, wiring) issue before I swap the new one in and have the same issue. The lack of the +12V signal to the rear has me stumped. I want to look for the relay wiring diagram to try to see which wires at the relay do which functions.
When I was doing my testing I ran into all kinds of readings back there which in retrospect is what sent me on the wild goose chase looking in the wrong places. Pulling the old actuator and testing it, or shaking it to hear if it's filled with rust and sand, wouldn't be a waste of time since you're putting a new one in anyway.
this was some of my experience: Differential lock ECU - https://forum.ih8mud.com/threads/differential-lock-ecu.1100168/
- Thread starter
- #7
Just an update to this thread - I pulled the old actuator to try to service it. I broke two bolts trying to get it apart so I just went ahead and installed the new actuator. The rear locker works perfectly now. I am not sure if the old one was just gunked up or faulty but since getting it open was problematic, and I needed it for a trip last weekend, I just went ahead and used the new one.
