Fuel level and coolant temp gauges showing under the actual value
 

Hello!

I have following issue: Both coolant temp and fuel gauges are showing under the actual values in the instrument cluster. The car is 2005 S60 2.5T AWD What makes this odd is that the speedo and tachometer seem to show the actual values, there is no fluctuation or any other oddities in the gauges at all, they just show little under the actual values. ie fuel lever goes to the max and the temp gauge does not show to north eventhouhgh the ECU says it is in the right operating temperature.

In the end the issues is nothing serious, but it is irritating and caused me to change the thermostat few times. Have you guys experienced this and is there any other solutions than changing the instrument cluster?

when you changed the thermostat, did you also change the engine coolant temp sensor (aka the ECT)? That's what feeds the DIM for your temp gauge. The fuel gauge is fed by a sending unit that's part of the pump, so unless its a total fail I'd leave that alone. Are you saying the fuel gauge never goes to E or doesn't move or just seems to indicate more (or less?) fuel than what's really in the tank?

I think you may need to consult a wiring diagram to see where the cluster gets its ground and perhaps pull the cluster to check/clean the connector(s). Should be some vids on YouTube on how to pull the cluster out (ie to change the backlighting bulbs).

I first changed the thermostat and after that I changed the whole housing including the ECT. But isn't it that ECT feeds ECU and ECU provides the infromation to the instrument cluster. Both the temp and fuel gauge show under the actual value, ie. fuel level is never MAX, although the tank is full. And other way around the warning light lights after the needle has passed the red are on the scale.

On the temp gauge the needle shows around the 82 degrees when normal operating temperature is 90 degrees and the ecu shows values ranging from 88-91 when the engine is hot (after a normal drive)- So something is wrong with the gauge or somehow it does not recieve the right signal, question is where to start the troubleshooting