Pinouts Question

[86LT1]

I'm trying to find out whats going on with my coolant temp sensor and so far I'm at a lose... What I've researched is that the pinout for this is the Gray connector #25... is this correct?? And second for some reason when i check for continuity i cannot get it to ring out. I dont know if something happened inside the harness or what. But second when I have my diagnostic hooked up to it, its reading the default -40, then when i apply ground to the wire #25 gray nothing changes on the diagnostic. I thought if i would apply ground to it, i should get it to work. If anyone can offer me any advice on how i can fix this problem or tell me what im doing wrong with this I would really appreciate it.

thanks,
Ben.

[ScottKnight]

I was tuning my car one day and noticed that with the key off, the ECT values were swinging wildly up and down. Figured the sensor took a dump, so being in a hurry, I just started trying resistors in the connector until I got a value that was 'somewhere in the vicinity of a running temp'. There are lots of values that will work (there is a chart for the range), but a 470 ohm resistor gave me like 68.5ºC.

When all was said and done, it just turned out that my terminals were corroded inside the connector. Once I cleaned them with a brass brush, everything worked perfectly.

If you are really working with the ECT sensor (as opposed to the sender for the gauge), it's probably not a good idea to be grounding it out since one of the terminals is a 5v reference from the PCM. Pretty sure you can hose the pullup driver with a direct ground. On the B-car, the ECT sensor (2-terminal connector) is in the water pump and the gauge sensor (1-terminal connector) is in the head by the dipstick.

If you want to check your harness, you just need to test continuity with a simple multimeter between the connector and the PCM. The PCM terminals will be B16 with a purple wire and C25 with a yellow wire. The purple wire is the ground, so you could also check it's resistance to ground with the PCM plugged in. The yellow wire is the 5v reference, so you could probe that for 5v with the key on.

Wiring issues suck. :puke: Good luck.

[86LT1]

thanks for the info. I'm going to start on that as soon as i get rid of my knock sensor issue.

[86LT1]

When you say "B"16 what color connector to the pcm does B stand for? And C.

thanks for the help scott

[ScottKnight]

I was wondering if you would come back and ask that. :D That is pretty easy info to come by with a search, but it's just about as easy to post it:
A is red
B is black
C is clear
D is blue

[86LT1]

haha, ya i just asked the ? and didnt take the time to search it, but thanks a lot for the help dude. I was also able to find the resistance values along w/ a chart from the shbox website.

[ScottKnight]

shbox is a great site that I have leeched plenty of info from.