Mechanics

TEMP GAUGE READING HIGH ALWAYS

1989 Honda Accord • 249,000 miles

My 89 Accord lxi temp gauge jumps to 1/2 as soon as the key is turned and soon rises to hot as the car warms up. It never overheats, but it want to know what the engine temp really is as my daughter will be taking the car off to college.
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Jbert
August 7, 2013.



I would use a manual guage to check or verify the actual temp of the motor.

It may be a bad sender unit or dash unit.

Roy

When I disconnect the wire from the temp sending unit, it goes up to 1/2 just as if it is plugged in. It doesn't rise anymore afterwards if the wire is not connected though.

Tiny
Jbert
Aug 7, 2013.
I would start by replacing the sender unit.

Roy

I actually have replaced the sender unit. The problem seems to be in the wiring between the sender unit and the gauge, Then gauge show 1/2 way to hot even when the wire to the sender unit is unplugged and even when I put the unit plugged in into ice water. Te gauge seems to be miscalibrated, but no one talks about that as a solution. Even when the motor is cold, it just goes to 1/2. I tested the gauge by grounding the sender unit wire and it went right to hot like it was supposed to.

Tiny
Jbert
Aug 7, 2013.
There is no calibration of the gauge unit. If you replaced the sender, then most likely you have a failed dash unit. Make sure the connector at the back of the instrument cluster is good.

Roy

I didn't think so. How would one go about getting to the instrument cluster. Pull the dash? If so, how would I do that?

Tiny
Jbert
Aug 7, 2013.
You dont think so? Did you check this already?

No, I meant I didn't think you could calibrate the gauge. I am trying to get to the gauge now.

Tiny
Jbert
Aug 7, 2013.
Most likely the dash unit is bad.

Roy

So, how do I test the temp gauge? I am getting a little tired of buying parts that aren't solving my problem. Thanks.

Tiny
Jbert
Aug 7, 2013.