Saab instrument cluster

[swansea v6]

My '06 Tid 9-3 has a weird issue where the thermostat gauge seems to stick halfway up the scale and sometimes shoot past the red zone. I have checked the actual temp with my obd scanner and the temps themselves are normal. Taking out the fuse for the cluster makes the gauge return to normal but the issue returns within a few miles.....any fixes or is it a new cluster? If it is a new cluster then is it a case of plug and play or does it need connecting go the car?

[paulmakin]

unplug the coolant temp sensor with the engine on and see if the gauge drops to zero. these do fail, replacement could be due. logic suggests that if the gauge drops then the sensor is ok. are the needles at rest before first start up?;

from what i can gather, the ECU digitizes the signal from the sensor and transfers it to the gauge via a stepper motor. unfortunately this means that the fault could be the sensor, the ECU, the I-bus, the stepper motor or the gauge. could be a sticky 'stat' as well i guess.

never had an SS (or, indeed, a diesel saab) myself but i do recall reading about temp gauge improbable readings quite a bit so hopefully someone who does know what they're talking about will be along shortly

i think a new cluster requires Tech 2 marrying - it does on the OG 9-3's

paul

[swansea v6]

Thank you for such a detailed reply! I have a day off today so first point of call will be to to change the coolant sensor and see what happens.

[griffin dai]

Mines been doing this the last couple years, fitted a new engine temp sensor & thermostat but still the same. Doesn't happen all the time but when it goes it keeps coming back 4 or 5 times until it settles down again and doesn't happen for a few months then.

I just pull the -ve battery cable for 15 mins and this usually resets it.

There is a fuse you can pull that resets it but I can't remember which one. Some info on this over on saabscene and uksaabs.

Basically.....needs a new instrument cluster and tech2'd to the car.

[swansea v6]

I have changed the thermostat and coolant sensor but again it keeps doing it....after fixing a leaky injector seal and gear turret bush I may get a new cluster.....I forgot how many small jobs crop up on these cars.....the egr valve was 99% blocked! And now I get an over boost eml warning if I dare hit 4000rpm.....spanners out again.