Ronnoc74

How do you tell if your temperature sensor is going bad?
The wires for the plug that plugs into my temperature sensor were dry rotted and they came off so I rewired it and my temp gauge won't read and the fan still won't come on.
I thought my fan relay was bad so I bought one of these for a temporary fix, http://www.autozone.com/autozone/par...26162_69567_0_ , and when I went to re-wire the temperature sensor plug the two wires for it touched accidentally and my fan kicked on, so I know my relay is good.
I'm pretty sure this means I need to replace my temperature sensor but I just want to double check and make sure I don't buy something I don't need to replace.

Former User

If you hope to get useful replies, then provide all relevant information about your car and engine:

https://honda-tech.com/forums/showpo...48&postcount=2

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---------------------------

Your engine has three different temp sensors:
1) The 2-wire fan switch on the thermostat housing
Under distributor:
2) The 1-wire temp sending unit for the cluster temp
3) The 2-wire temp sensor for the ECU

Which are we talking about?

Ronnoc74

Sorry,

'93 Civic Hatch with a D15B8 (soon to be a z6 mini me swap)

I'm talking about the 2 wire fan switch on the thermostat housing that the wires came off of.
When I touch the two wires together the fan turns on, but the fan won't turn on normally.

Former User

Yes, you likely need to replace the fan switch on the thermostat housing.

The temp gauge problem is separate. Do the tests on the gauge and 1-wire temp sender unit under the distributor:

Ronnoc74

What does it mean to test the wires for an open?
I did what it said on the left side of the page and my temp gauge didn't move. I had a friend look at the gauge while I held the ground on the wire and he said that the gauge twitched twice when I moved the wires around a little but didn't move like specified.
It says to replace the gauge if that test didn't work but I know the gauge works because I took the car down the road and back it was working but when I pulled in the driveway I hit a bump and the gauge just dropped...

Former User

An open is basically a broken wire. That wire runs from the sending unit to the cluster. Use a multimeter to test whether there is continuity between both ends of that wire. If so, the cluster or temp gauge is bad.

Ronnoc74

I did some more searching on here and in a similar thread you said to ground the wire to the engine, I didn't do that in my test. Would it make a difference whether I grounded it to the frame or the engine?

Ronnoc74

If I grounded the pin for the temp gauge, would that also make the gauge go up or tell me if there's an open in the wire?

Former User

^Possibly, but describe to me how you plan to do this.

Do you have a multimeter? If so, I can also tell you how to do the test.

Ronnoc74

I did an '00 ls cluster swap and the way I wired it up allows me to connect and disconnect the wires.


I've got a multimeter,

Ronnoc74

How do I do the test with the multimeter?

Former User

Unplug the sender unit and cluster. Set your multimeter to measure Ohms on the 200 Ohm scale. Firmly ground the terminal in the sender unit connector to the engine. From inside the car, touch one meter probe to the corresponding wire terminal in the cluster connector and the other meter probe to the metal frame under the dash. Post the Ohm reading. It should be less than 100 Ohms.

Ronnoc74

I did the test and I had a friend help me out with grounding the wire. I put the multimeter on 200 Ohms got a reading anywhere between 5.2 and 3.4 depending on if he moved the ground around. Are those good numbers? What did this test figure out?

Former User

The test says the wire is good (has low resistance), indicating that the temp gauge or cluster is the problem.

Ronnoc74

That's exactly what I wasn't wanting to hear.
I don't understand how the temp gauge could be working then all of a sudden go dead like it did...

EDIT: The rest of the cluster works, at least the Tach and Speedo, I haven't put enough gas in it yet to be able to tell if the gas gauge works.
Would this mean I have to get a whole new cluster with the temp gauge being bad, or is there a way to fix it?

jeremyhughes

iTrader: (1)

Take the casing off the cluster, then remove the screws that hold the temp/gas gauge in place and just replace that, you shouldn't need to replace the entire cluster, just the faulty segment of it, if you are careful enough you can just remove the temp gauge itself (remove the case from the cluster, remove the fuel/temp gauge combo, remove the needle (careful part) and unscrew the little voltmeter from the back of the gauge face (all the different electrical gauges are task-specific voltmeters essentially))and not the fuel gauge also.

Former User

Old thread^

Closed.