located the temp gauge wire coming out of the pcm for my 2001 accord ex v6. when I put ground to it thru my test light the needle jumps to h. what do I need to do from here to get my gauge working. if I run a wire from my battery to this wire should it work/ please help me im so close to getting my gauge working so I don't overheat during the summer. thanks guys

 

What car are you driving, exactly? If your car was going to overheat it would've already done so. The way I understand, the temperature gauge you see in the dashboard is only for you to look at and not used by the vehicle to control when to turn on the radiator fans or open the thermostat. The thermostat opens by itself if the coolant gets too hot due to expansion of a special material/metal in it. It would be nice to have a temp sensor working at your dashboard but I think this is not critical. Heck, my Subaru Outback does not even show me my coolant temperature!

Perhaps, you are not suppose to supply power to the sensor. Are there only two wires going to the sensor? If so, maybe the sensor works on piezoelectricity so it would generate it's own voltage and send it to your temp gauge. There are temperature sensors that run off of a thermocouple so those too would generate their own voltage.
Could it be that your sensor went bad and just needs to be replaced? Having said that, perhaps this temperature sensors works off of a potentiometer so then the sensor would indeed require eternal power supplied to it.

Try to get a spec sheet for the temperature sensor and then you'll know for sure what it runs off. Or you can experiment (get creative) and find out whether this temperature sensor needs power or the sensor "makes its own power".

 

I thought the temp sensor was located near where the distributor that fed that gauge? Or is that only older accords?

 

That would be helpful if he had an I4

 

My point is that I thought it wasn't coming from the computer, it's coming from a separate sensor.

v6

 

To be worth its weight in gold, so to speak, you want the coolant temperature reading displayed at the dashboard to come from a dedicated sensor (independent of where the computer gets its reading). That way, if the computer sensor readings are off you have a backup sensor to "raise the alarm". So yes, it should be coming from a separate/dedicated sensor if done right. :D

 

on the 2001 accord ex v6 there is no temp sending unit that's what im having trouble with. from my research I believe the temp gauge wire comes out of the pcm at connector a1 (yellow/green) so what does that wire need in order to work? DAVESMIT that's an interesting thought the sensor does have only two wires I was under the impression that one wire runs thru the multiplex were it gets grounded and the other wire goes to the pcm to a1 then to to temp gauge at c2. I diddnt read that anywere that is just strickly my thought. anyone know what is right or want to add input?
ty to all who responded.ty 99STOCKCIVIC for the diagram but I have a v6. anyone have a diagram for ect wiring for a 2001 ex v6?

 

I see now after reading a bit. There is a sensor under the distributor, but it goes to the computer first. However, it could be bad.

You can see where it is in this pic

 

hey civic, that's what I thought but the 2001 accord ex v6 has no sending unit and my car has coil packs no distributor. this is the v6 model

 

I belive the ect wire goes in the pcm and out of a1 connector at pcm (yellow/green wire) to temp gauge at c2 connector behind cluster. I just have nothing coming out my temp sensor. how can I troubleshoot this? ty

 

lol I ment nothing coming out of my temp gauge my temp sensor is working fine I troubleshooted that part of it. I believe it goes in pcm at c26 and out at a1. I have 12 volts at gauge wire on multimeter when car is on just nothing happening

 

Sorry, I was thinking you could just tap into the wire and run it to your gauge for now (or an aftermarket gauge ).

 

don't be sorry man im just happy for your input. everything helps/I actually found the diagram I was looking for but still no temp gauge no matter what I do. im starting to think it could be a bad pcm because if the temp gauge wire comes out of the pcm to the gauge at a1 then there wpuld be no wire to trace back/ the signal should be coming from the pcm and it is not. I even tried running a new wire from the pcm to the gauge and still nothing. I know for a fact my ect wire going in the pcm at c26 is deff working after running tests so the 5 volt signal is deff getting to the pcm but it gets lost there. I got nothing coming out

 

TL;DR
ECT to C108 connector to PCM C26 (red/wht) and to gauge C2(Yel/Grn)

If you are not getting a signal at the cluster it might be the C108 connector being goofy on the gauge side.




Also verify the ground is good.
C18 SG2(GRN/BLK)

 

ty MIKE awesome info going outside to check on this connection right now. gonna unclip it inspect her and clean her. ill keep u updated.

 

why no green/ yellow at the connector? does the green yellow go right from pcm to gauge/

 

From PCM C24 pin the YEL/GRN wire should go to the ECT gauge C2. There are a couple connectors in between the PCM and gauge C101 and C204, check those for loose pins and corrosion.
If you are getting a proper signal up to gauge cluster(C2) and a proper ground then the gauge should work.

Gauges on the 00-02 models come from the PCM.
Previous 90-99 models used divorced gauge and ECM/PCM sensors and harness.

If an aftermarket head unit was hacked in they may have damaged or cut the wire to the gauge. Verify there is no modification of the wire harness that may interfere with a secure signal to/from the gauge.

 

my car is a v6 it is blank on c24. I believe the gauge wire is a1 coming out of pcm. if I put a ground signal to a1 my gauge goes to h but the gauge is not working. how do I troubleshoot that?

 

but I can hook the ect sensor wire into a1 and get the gauge working correctly but it makes my car run like crap and idle high so my gauge is not broken it deff works its an electrical prob. I have no temp gauge sending unit in this car im wondering if maybe the pcm is the prob? I tested the ect sensor and she is good to the pcm at c26. how can I test to see if im good coming out of my pcm to my gauge cluster?

 

what I decieded to do is order the temp sending unit for the 99 model (in pic above) and im just gonna tap it in somewere in my upper radiator hose and run the wire to my gauge at c2.im just going to completely bypass the pcm. im hoping that should work right? any ideas the best/easiest place to install it and how should I do it? u think I can get away with getting just a piece of 1"1/4 pipe and drilling a hole in the top and threading the sensor into it tight then gluing it?