P0325

DTC P0325:

DIAGNOSTIC TROUBLE CODE PO325
KNOCK SENSOR, MALFUNCTIONING OR NOT WORKING AT ALL

Fault symptom
The car only runs at basic charging pressure, timing continuously retarded.

NOTE: Saab Trionic does not have a conventional knock sensor. The signal comes from the ignition discharge module.

Condition
No knocking signal for 10 seconds.

Diagnostic procedure
1. Connect an ISAT scan tool.

- Start the engine.
- Select the "KNOCK SENSOR" command on the ISAT scan tool menu "READ FUNCTIONS".

The ISAT scan tool must show a number between 0 and 2.55 V, depending on the level of the knocking signal.

At idling speed the ISAT must show 0.06-0.10 V.

With a fast accelerator setting, the display on the ISAT may vary between 0.06-2.55 V.

The measurement must show that a signal is present. If there is a discontinuity in the signal lead, 0.06 V is normally shown regardless of the accelerator setting.

- If there is a knocking signal, continue with step 3.
- If there is no knocking signal, continue with step 2.

DTC P0325:

2. Check the lead between connecting pin 7 on the ignition discharge module and pin 44 on the ECM for open circuit, short circuit and any stray current.

- If any measured value is incorrect, check and if necessary remedy the fault in the wiring. Pay special attention to the backing-out of connector sleeves and connector pins.
- If the measured value is correct, continue with step 3.

3. Erase the diagnostic trouble code and drive the car to see whether the DTC is generated again.

- If the diagnostic trouble code is generated again, install a new ignition discharge module and then drive the car to see whether the diagnostic trouble code is generated again.
- If the diagnostic trouble code recurs, continue at "Procedure before replacing ECM", after refitting the ignition discharge module.
- If the diagnostic trouble code is not registered, the action taken is correct. Otherwise the fault is intermittent in nature.