2004 H2 Engine Temp Gauge goes Nuts

[HMH2SUT]

I have had the same problems recently. all guages are shot, I will be sending it out soon for repair,but would the faulty guages throw codes?

I have the p1258 code now.
any suggestions on the p1258 repair? temp sensor? fan?...
It's 10 degrees outside today first got "engine coolant hot" then "engine overheated" then "reduce power.." any help would be appreciated thanks

[Easy Ed]

Info on P1258 from a 2003 SM. Hope it helps.

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[Olfart]

Originally Posted by HMH2SUT

I have had the same problems recently. all guages are shot, I will be sending it out soon for repair,but would the faulty guages throw codes?

I have the p1258 code now.
any suggestions on the p1258 repair? temp sensor? fan?...
It's 10 degrees outside today first got "engine coolant hot" then "engine overheated" then "reduce power.." any help would be appreciated thanks

The Engine Temp gauge being bad should not result in a code. You can remove the instrument cluster from the truck and still drive it normally without any codes coming up. Besides a bad temp gauge stepper motor...which will be corrected when you send the cluster out for repair....you now seem to have a real engine overheat condition. Check coolant level, belts, thermostat.

[HMH2SUT]

Thanks for the help guys. I need to pick myself up one of those wonderful books!. I think it was my ECT sensor... I replace the ECT, thermostat and flushed with dexcool. So far no problems it's running at 190 and the needle is steady again no more jumping. I tested the thermostat and it opened at 190, It was flushed in 12/08 so Im guessing it was the ect. I don't know how to test the ect so Im only guessing that was it... Thanks again

[Easy Ed]

Sorry, I tried to find that info for checking the ECT but did not see it in the SM. It just said to hook up the Tech II and blah, blah, blah

The ECT can be checked with a OHM meter for resistance at different temps but I did not know the correct readings for our trucks.

Hope the ECT was it.

Ed

Originally Posted by HMH2SUT

Thanks for the help guys. I need to pick myself up one of those wonderful books!. I think it was my ECT sensor... I replace the ECT, thermostat and flushed with dexcool. So far no problems it's running at 190 and the needle is steady again no more jumping. I tested the thermostat and it opened at 190, It was flushed in 12/08 so Im guessing it was the ect. I don't know how to test the ect so Im only guessing that was it... Thanks again