DTC P0325 Knock Sensor Module Performance. Buick Riviera 1999

For 1990-2009 cars only

Makes 🢒 Buick 🢒 1999 🢒 Riviera 🢒 DTC 🢒 DTC P0325 Knock Sensor Module Performance

Engine Controls Components
Engine Controls Schematics
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The PCM contains integrated Knock Sensor (KS) diagnostic circuitry. Input signals from the knock sensors are used to detect engine detonation, allowing the PCM to retard Ignition Control (IC) spark timing based on the amplitude and frequency of the KS signal being received. The knock sensors produce an AC signal under all engine operating conditions. During engine operation, the PCM calculates the average voltage of each knock sensor's signal. If the PCM malfunctions in a manner which will not allow proper diagnosis of the KS circuits, DTC P0325 will set.

Conditions for Running the DTC

•	No TP sensor, VSS, CKP, MAF, or ECT DTCs are set.

•	Engine speed is between 1000 and 3000 rpm.

•	Throttle angle is greater than 15%.

•	Engine load is greater than 45%.

•	Engine coolant temperature is greater than 75°C (167°F).

•	Maximum spark retard is less than 15 degrees.

•	System voltage is greater than 9 volts.

Conditions for Setting the DTC

•	The PCM detects a malfunction in the integrated knock sensor diagnostic circuitry which will not allow proper diagnosis of the knock sensor circuits.

•	Above conditions are present for at least 1 second.

Action Taken When the DTC Sets

•	The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.

•	The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

Conditions for Clearing the MIL/DTC

•	The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.

•	The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

•	The DTC can be cleared by using a scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

This DTC indicates an internal PCM problem.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed. Refer to PCM Replacement/Programming .

Step	Action	Value(s)	Yes	No
1	Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?	--	Go to Step 2	Go to Powertrain On Board Diagnostic (OBD) System Check
2	Important:: If an engine knock can be heard repair the engine mechanical problem before proceeding with this diagnostic. Refer to Engine Noise Diagnosis . Operate the engine within conditions specified in diagnostic support. Refer to Conditions for Setting the DTC. Monitor Specific DTC info for DTC P0325 until the DTC P0325 test runs, using a scan tool. Does scan tool indicate DTC P0325 failed this ignition?	--	Go to Step 4	Go to Step 3
3	Turn ON the ignition. Review and record scan tool Fail Records data for DTC P0325. Operate vehicle within Fail Records conditions. Monitor Specific DTC info for DTC P0325 until the DTC P0325 test runs, using a scan tool. Does scan tool indicate DTC P0325 test failed this ignition?	--	Go to Step 4	Go to Diagnostic Aids
4	Important:: The replacement PCM must be reprogrammed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Is the action complete?	--	Go to Step 5	--
5	Review and record Fail Records data Clear the DTCs. Operate the vehicle within Fail Records conditions. Monitor Specific DTC info for DTC P0325 until the DTC P0325 test runs, using a scan tool. Does the scan tool indicate DTC P0325 test failed this ignition?	--	Go to applicable DTC table	System OK