Check ECM Signal

Start the engine.

Measure the voltage between ECM connector and engine ground.

Connector & terminal 

Saab 9-2X 2.5i Linear: 

(B134) No. 10 (+) - Chassis ground ( - ): 

Saab 9-2X 2.0T Aero: 

(B137) No. 9 (+) - Chassis ground (- ): 

Is the voltage 0 or 14 V or more? 

YES. Go to  CHECK HARNESS BETWEEN COMBINATION METER AND ECM  . 

NO 

Check the ECM.