Circuit/System Testing
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
- Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
- If an engine mechanical noise can be heard, repair the condition before proceeding with this diagnostic. Refer to Symptoms - Engine Mechanical .
- With the ignition OFF, disconnect the affected knock sensor.
- Test for an intermittent and for a poor connection at the affected KS.
- Measure for infinite resistance from the sensor signal terminal on the knock sensor to a good ground and the low reference terminal on the knock sensor to a good ground with a DMM.
- If resistance does not measure infinite ohms at both terminals than replace the affected KS.
- Turn the ignition ON, engine OFF. Measure for 4.2 volts from the KS signal circuit to a good ground and the KS low reference circuit to a good ground with the DMM.
- If over 4.2 volts with the ignition OFF disconnect the control module and test the KS signal circuit or the KS low reference circuit for a short to voltage.
- If under 4.2 volts with the ignition OFF disconnect the control module test the KS signal circuit or the KS low reference circuit for an open, short to ground or high resistance.
- Test for intermittent or poor connections at the control module.
- If all circuits test normal then replace the control module.
P0326
- Inspect for a loose or broken vehicle accessory or accessory bracket.
- Inspect for excessive engine mechanical noise.