Been messing around with the cluster LEDs on my 98 accord coupe, and ran into an issue.

*see here for LED conversion for 98-2002*
https://www.hondaaccordforum.com/for...ad.php?t=35600


So I now own 3 98-02 gauge clusters. My original, which is totally non-functional except for the speedo & gas gauge. I bought a replacement for my original, because i had tried my own makeshift LED installation, and then none of the lights ever worked again, even with fresh bulbs. Turns out the replacement is from a 01 4-door. Everything worked, even the two front door lights, except for the temp gauge. shot RIGHT up to hot. Thought it might have been a faulty cluster, so i got a fresh one. One that was tested, 100% functional. This one was off a 99 coupe -- and looks a little different. The gauges are grey and the numbers are different, but for the most part it looks exactly the same. Same thing, temp shoots right up to hot in less than 30 seconds of the car being turned on. I know my car is not overheating, but it is nice to know when the engine is warm or cold for certain testing purposes. Any input on this, guys??? Could i have f'd up the "thermometer"? or whatever by switching clusters so many times? I have uninstalled/reinstalled these three clusters for testing of the LEDs (which i now have working, see above link) at least 100 times, including all 3 clusters. Wires all seem intact. It just seems weird since it happened on both new clusters.

Thanks in advance!

 

Is your car a V6, I4, LX, DX, EX...

I would unplug the connector to the engine coolant temperature sending unit. Make sure the electrical connector does not touch ground.

The temperature sending unit should be bolted into the cylinder head near the distributor. It may be bolted into the thermostat housing. It will only have one wire going to it.

Turn the Key to the II position (don't try to start). If the temperature gauge goes to hot immediately, then that wire is grounded somewhere between the cluster and the sending unit. You can verify by unplugging the cluster and the sending unit. Test for continuity to ground at the sending unit pin and body ground (like a valve cover bolt).

If the gauge does not move, then I would replace the sending unit.

 

Mine is an EX, 4 cyl. Not even sure about the ones that the replacement came off of. Thanks for the reply, plan on checking out what you suggested tomorrow.

EDIT: and yes, on ingnition II, the temp shoot up immediately, without engine start.

 

Did you ever get this figured out? I’m in the same boat currently. I’ve used a few clusters to get all the lights working and I’m having constant high readings for no reason. Fans not kicking on as well.