back up lights

[goin69]

I have a 1990 240sx. I have just bought this car. I have slight problem though, I can not seem to find out why my back up lights will not work. I was hoping that someone might be able to share some ideas that might help me get started on trying to find the right solution. Thank you for your time.

[Axel Grungy]

is it safe to assume youve checked all fuses/bulbs??

[goin69]

yes i have done that

[navysnail]

reverse sensor in the transmission, its a $15 dollar part at NAPA and very easy to install

[bcar240]

when I got my car I also noticed the reverse lights didn't work. I had the trunk apart looking at the lights and went to check the fuse and somebody had forgot to put one in the spot for the lights! Anyway, since that is not the problem, I would start at the lights and use a multimeter to check whether there is any current in the fixtures. I would start working my way forward from there. Checking every junction, spilce you can get to. Sometimes the simplest parts go bad or break.

[goin69]

and if turns out to be the sensor. how would i go about changing this out

[navysnail]

unbolt it from the transmission (assuming you have a manual) then screw the other one in. you will loose a little bit of gear oil, but if your quick about it you will be fine. also, put some thread sealant on the threads of it so it doesnt leak. you can test the sensor on it now with a multi meter, just check the resistance of it with the transmission in and out if reverse, it sohould be 0 or somthing around that when in, and wont flow when out of reverse