0493

0493-KNOCK SENSOR SYSTEM ERROR





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the engine running and battery voltage greater than 10 volts.

- Set Condition:
The PCM detects that the input voltage is not within a specified range based on operating conditions.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE

NOTE: Diagnose and repair any system voltage or sensor supply voltage DTCs before continuing with this test.

Turn the ignition on.
With the scan tool, read DTCs.
Record all DTC and applicable Freeze Frame information.
With the scan tool, clear DTCs.
Cycle the ignition off for at least one minute.
Start the engine and allow it to reach operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose fitting clothing. Failure to follow these instructions can result in personal or fatal injury.

With the scan tool, read DTCs.
Does this DTC reset?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking for an Intermittent DTC

2. ENGINE MECHANICAL CONDITION
Inspect the engine and any related components for a condition that could cause an engine knocking noise, such as a worn piston or connecting rod, or worn or loose accessory pulleys or brackets.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 3

3. KNOCK SENSOR WIRING AND CONNECTORS
Turn the ignition off.
Disassemble the engine components as necessary to gain access to the Knock sensors
Check the circuits for an intermittent short to ground, short to voltage, open circuit, or high resistance.
Inspect the connectors for damage, corrosion, or any condition that could disrupt the sensor signal.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Go to 4

4. KNOCK SENSORS
Turn the ignition off.
Replace both Knock sensors.
Re-assemble the engine components that were disassembled to gain access to the Knock sensors
Turn the ignition on.
With the scan tool, clear DTCs.
Cycle the ignition off for at least one minute.
Start the engine and allow it to reach operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose fitting clothing. Failure to follow these instructions can result in personal or fatal injury.

With the scan tool, read DTCs.
Does this DTC reset?

Yes

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Test complete.
- Perform the PCM Verification Test.Powertrain Verification Test