Temperature gauge not working?

1994 DODGE RAM
300,000 MILES • 5.9L • V8 • 2WD • AUTOMATIC
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OLLIE2022
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  • 49 POSTS
Replaced both coolant temperature sensors beside the thermostat which is new still no gauge. Is it common to go out or should intrace the wire or replace it? I'm flustered.
Nov 28, 2022 at 7:50 AM
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JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,240 POSTS
Hi,

There is a chance the wiring is causing issues, the PCM isn't receiving a signal, or the gauge is faulty.

Here is what to do: At the ECT, there are two wires. One is tan with a black tracer and the other is blue with a light blue tracer.

The tan/black wire provides a 5v reference from the PCM. With the key on, confirm that is the case.

The blue/light blue wire is a ground reference from the PCM. Again, with the key on, check that wire for continuity to ground.

Let me know what you find.

Take care,

Joe

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Nov 28, 2022 at 2:11 PM
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OLLIE2022
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  • 49 POSTS
Ect??
Nov 29, 2022 at 3:25 AM
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JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,240 POSTS
Hi,

I'm sorry. ECT stands for engine coolant temperature sensor. I apologize. I'm used to using technical jargon in the shop.

Let me know what you find or if you have other questions.

Take care,

Joe
Nov 29, 2022 at 11:14 AM
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OLLIE2022
  • MEMBER
  • 49 POSTS
10-4.
Nov 29, 2022 at 2:11 PM
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