RPM and coolant gauges not working

When I purchased this truck I was told by the sales person that the RPM Gauge and Coolant Gauge does not work. Apparently the previous owner swapped out the cluster before and still did not work (not sure how true that is). I hooked up a OBD2 scanner and I’m able to get readings for the RPM and coolant temp. Could it possibly be a faulty instrument cluster that was never changed or maybe an electrical issue directly to the gauge? I need all the help I can get so please let me know your ideas, I’d greatly appreciate it!

*Side Note: speedometer and fuel work perfectly. Including all the lights.

 

@caribe makaira might be able to help.

 

See what part number you have on the cluster, they could have the wrong part number. Newer trucks (12+) sent RPM and Coolant Temp over CAN and older ones had dedicated lines for Coolant Temp and RPM.

 

So once I get it removed, search up the part number to see if it’s for the same year of the truck? If not, its probably the incorrect one ?

 

Yes.

My only other theory is it has the wrong part number PCM in it but that would be very unusual.

Can your scanner talk to the cluster and see what input it's seeing?

 

I don’t think so I was only able to see the live readings it was putting out. Seeing that it was giving me results I was leaning towards the actual cluster.

 

Just got home from work and took the cluster out and it is the OEM
Has the same
83800-04f60-B

 

That's the correct part number for a 2012 2.7L Automatic.

 

Now time to forgive out what else could be the problem thanks for the suggestion

 

I'll have to look at some stuff when I get home tonight, there's not alot we can test with limited tooling but I'll see what I can come up with.

 

I’m going to keep looking into this and see if I find anything. Thank you for your help. It just bothers me that I can’t even tell if my cars overheating with having a scanner attached the whole time. Let alone not being able to see my RPM

 

Reading material

 

More

 

I think we need to check the PCM part number as well and see if it's correct.
Just to be clear everything else but the tach and temp gauge works and there are no warning lights correct?

This applies only to trucks built before December of 2010, after December 2010 production Coolant Temp and Tach Signal were sent over CAN to the Meter instead of dedicated lines.

 

The ABS light and Traction light is also on. I’ll take a look at the PCM part number once I get home from work.