Mazda 2002 6 Workshop Manual page 226

Diagnostic procedure
STEP
1 PERFORM DTC CONFIRMATION PROCEDURE
• Perform DTC CONFIRMATION PROCEDURE.
(See F–66 DTC CONFIRMATION
PROCEDURE.)
• Is same DTC present?
2 INSPECT POOR CONNECTION OF ECT
SENSOR CONNECTOR
• Turn ignition key to OFF.
• Disconnect ECT sensor connector.
• Inspect for poor connection (damaged, pulled-
out pins, corrosion, etc.).
• Are there any malfunctions?
3 CLASSIFY ECT SENSOR MALFUNCTION OR
HARNESS MALFUNCTION
• Connect WDS or equivalent to DLC-2.
• Access ECT PID.
• Connect a jumper wire between ECT sensor
terminals A and B.
• Verify ECT value
• Is voltage below 4.5 V?
4 INSPECT ECT SENSOR SIGNAL CIRCUIT FOR
SHORT TO POWER
• Turn ignition key to ON (Engine OFF).
• Measure voltage between ECT sensor terminal
A (harness-side) and body ground.
• Is there voltage B+?
5 INSPECT POOR CONNECTION OF PCM
CONNECTOR
• Disconnect PCM connector.
• Inspect for poor connection (damaged, pulled-
out pins, corrosion, etc.).
• Are there any malfunction?
6 INSPECT ECT SENSOR SIGNAL CIRCUIT FOR
OPEN CIRCUIT
• Inspect continuity between ECT sensor
terminal A (harness-side) and PCM terminal
1M.
• Is there any continuity?
7 INSPECT ECT SENSOR GROUND CIRCUIT
FOR OPEN CIRCUIT
• Inspect continuity between ECT sensor
terminal B (harness-side) and PCM terminal
2H.
• Is there any continuity?
8 VERIFY TROUBLESHOOTING OF DTC P0118
COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Clear DTC from PCM memory using WDS or
equivalent.
• Perform KOEO/KOER self-test.
(See F–66 KOEO/KOER
• Is same DTC present?
9 VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
(See F–66 AFTER REPAIR
• Is there any DTC present?
End Of Sie
ON-BOARD DIAGNOSTIC
INSPECTION
SELF-TEST.)
PROCEDURE.)
Yes Go to next step.
No Intermittent concern exists. Go to INTERMITTENT
CONCERN TROUBLESHOOTING procedure.
(See F–227 INTERMITTENT CONCERN
TROUBLESHOOTING.)
Yes Repair or replace terminal, then go to Step 8.
No Go to next step.
Yes Replace ECT sensor, then go to Step 8.
No Go to next step.
Yes Repair or replace harness for short to power, then go to
Step 8.
No Go to next step.
Yes Repair or replace terminal, then go to Step 8.
No Go to next step.
Yes Go to next step.
No Repair or replace harness for open, then go to Step 8.
Yes Go to next step.
No Repair or replace harness for open, then go to next step.
Yes Replace PCM, then go to next step.
(See F–43 PCM REMOVAL/INSTALLATION.)
No Go to next step.
Yes Go to applicable DTC troubleshooting.
(See F–67 DTC TABLE.)
No Troubleshooting completed.
ACTION
F–97
F