A343F electrical connector questions / flashing O/D light

[GBinAZ]

Question for you A343 transmission gurus. I am looking for the source of my flashing dashboard O/D light after ignoring it for a decade. It started flashing after i had the under carriage pressure washed. No symptoms when driving over all these years, but its annoying. Fluid has been changed very regularly via drain and fill, and is a nice red, not brown at all, and never has been. I got under the truck to check the transmission electrical connectors and found two things that seam strange but may be nothing.

This is a left hand drive 95 FZJ80

One unplugged connector on a wiring harness visible from the drivers side of the vehicle with no place to plug it in nearby from what I can see. The connector is white and in the left side of the first pic.

And a second connector on the passenger side, on what looks like a fitting, with nothing plugged in to it.

The connecter on the harness feels like its too far away from the connector on the fitting to plug in and I dont want to make a mistake.

My plans is to clean all the connectors with electronics cleaner once know what to do, if anything, with the unplugged connectors

Any help would be appreciated.

 

[ajax1]

That plug needs to go to the other side it is not routed correctly and plug into where you are showing in your second pic

 

[ajax1]

 

[GBinAZ]

View attachment 4043026

View attachment 4043026

Awesome. I will clean the connectors reroute the cable and see what happens.

Much appreciated.

 

[Malleus]

The connector on the fitting is the transmission temperature sensor. No wonder your ECM is complaining...

 

[GBinAZ]

I re-routed the harness, a total PITA, and reconnected the temp sensor O/D light stopped flashing.

 

[GBinAZ]

The connector on the fitting is the transmission temperature sensor. No wonder your ECM is complaining...

I am surprised that it never set the check engine light, just flashing O/D light. My truck has a 5/95 build date, not sure what the ECM firmware was capable of at that time. I am lucky that nothing catastrophic happened during my decade of ignoring the flashes.

 

[Malleus]

The TCM part of the ECM doesn't have a connection with the MIL (check engine light). The only indication you have of a transmission problem, other than overheating, is the O/D light. The transmission won't overheat in normal driving, because of the cooling system, including the oil cooler mounted in front of the radiator.

It's probably time to change the ATF, if you haven't already done that. It's only good for two years, under normal conditions. And by change, I mean flush teh entire cooling system, not just pulling the drain plug.