Mazda 6. Manual - part 143

F–94

ON-BOARD DIAGNOSTIC 

End Of Sie

DTC P0117

A6E397001084W16

5

INSPECT POOR CONNECTION OF PCM 
CONNECTOR

• Turn ignition key to OFF.

• Disconnect PCM connector.

• Inspect PCM terminals 2E and 2H (harness-

side) for tightness using feeler tool.

• Are there any malfunction?

Yes Repair or replace terminal, then go to Step 9.

No

Go to next step.

6

INSPECT IAT SENSOR SIGNAL CIRCUIT FOR 
OPEN CIRCUIT

• Inspect continuity between MAF/IAT sensor 

terminal D (harness-side) and PCM terminal 
2E.

• Is there any continuity?

Yes Go to next step.

No

Repair or replace harness for open, then go to Step 9.

7

INSPECT IAT SENSOR GROUND CIRCUIT FOR 
OPEN CIRCUIT

• Inspect continuity between MAF/IAT sensor 

terminal E (harness-side) and PCM terminal 
2H.

• Is there continuity?

Yes Go to next step.

No

Repair or replace harness for open, then go to next step.

8

VERIFY TROUBLESHOOTING OF DTC P0113 
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 SELF-TEST

.)

• Is same DTC present?

Yes Replace PCM, then go to next step.

(See 

F–43 PCM REMOVAL/INSTALLATION

.)

No

Go to next step.

9

VERIFY AFTER REPAIR PROCEDURE

• Perform “After Repair Procedure”.

(See 

F–66 AFTER REPAIR PROCEDURE

.)

• Is there any DTC present?

Yes Go to applicable DTC troubleshooting.

(See 

F–67 DTC TABLE

.)

No

Troubleshooting completed.

STEP

INSPECTION

ACTION

DTC P0117

ECT circuit low input

DETECTION 

CONDITION

• PCM monitors ECT sensor signal at PCM terminal 1M. If PCM detects ECT sensor voltage below 0.2 V, 

PCM determines that the ECT sensor circuit has malfunction.

Diagnostic support note

• This is a continuous monitor (CCM).

• MIL illuminates if PCM detects the above malfunction condition during first drive cycle.

• PENDING CODE is available if PCM detects the above malfunction condition.

• FREEZE FRAME DATA is available.

• DTC is stored in the PCM memory.

POSSIBLE 

CAUSE

• ECT sensor malfunction

• Connect or terminal malfunction

• Short to ground circuit between ECT sensor terminal A and PCM connector terminal 1M.

• Short each harness ECT signal circuit and ECT ground circuit.

• PCM malfunction

ON-BOARD DIAGNOSTIC 

F–95

F

Diagnostic procedure

STEP

INSPECTION

ACTION

1

PERFORM DTC CONFIRMATION PROCEDURE

• Perform DTC CONFIRMATION PROCEDURE.

(See 

F–66 DTC CONFIRMATION 

PROCEDURE

.)

• Is same DTC present?

Yes Go to next step.

No

Intermittent concern exists. Go to INTERMITTENT 
CONCERN TROUBLESHOOTING procedure.
(See 

F–227 INTERMITTENT CONCERN 

TROUBLESHOOTING

.)

2

INSPECT TERMINAL BENT

• Turn ignition key to OFF.

• Disconnect ECT sensor connector.

• Inspect for bent of ECT sensor terminals A and 

B (part-side).

• Is there any malfunction?

Yes Repair or replace terminal, then go to Step 6.

No

Go to next step.

3

CLASSIFY ECT SENSOR MALFUNCTION OR 
HARNESS MALFUNCTION

• Connect WDS or equivalent to DLC-2.

• Access ECT PID.

• Verify ECT value when disconnecting ECT 

sensor connector.

• Does ECT value change?

Yes Replace ECT sensor, then go to Step 6.

No

Go to next step.

4

INSPECT ECT SIGNAL CIRCUIT FOR SHORT 
TO GROUND

• Turn ignition key to OFF.

• Inspect continuity between ECT sensor 

terminal A (harness-side) and body ground.

• Is there any continuity?

Yes Repair or replace harness for short to ground, then go to 

Step 6.

No

Go to next step.

5

INSPECT IAT CIRCUIT FOR SHORT 
HARNESSES

• Inspect continuity between ECT sensor 

terminal A and B (harness-side).

• Is there any continuity?

Yes Repair or replace harness for short, then go to next step.

No

Go to next step.

DTC P0117

ECT circuit low input

F–96

ON-BOARD DIAGNOSTIC 

End Of Sie

DTC P0118

A6E397001084W17

6

VERIFY TROUBLESHOOTING OF DTC P0117 
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 SELF-TEST

.)

• Is same DTC present?

Yes Replace PCM, then go to next step.

(See 

F–43 PCM REMOVAL/INSTALLATION

.)

No

Go to next step.

7

VERIFY AFTER REPAIR PROCEDURE

• Perform “After Repair Procedure”.

(See 

F–66 AFTER REPAIR PROCEDURE

.)

• Is there any DTC present?

Yes Go to applicable DTC troubleshooting.

(See 

F–67 DTC TABLE

.)

No

Troubleshooting completed.

STEP

INSPECTION

ACTION

DTC P0118

ECT circuit high input

DETECTION 

CONDITION

• PCM monitors ECT sensor signal at PCM terminal 1M. If PCM detects ECT sensor voltage above 4.6 V, 

PCM determines that ECT sensor circuit has malfunction.

Diagnostic support note

• This is a continuous monitor (CCM).

• MIL illuminates if PCM detects the above malfunction condition during first drive cycle.

• PENDING CODE is available if PCM detects the above malfunction condition.

• FREEZE FRAME DATA is available.

• DTC is stored in the PCM memory.

POSSIBLE 

CAUSE

• ECT sensor malfunction

• Open circuit between ECT sensor terminal A and PCM terminal 1M

• Short to power circuit between ECT sensor terminal A and PCM terminal 1M

• Open circuit between ECT sensor terminal B and PCM terminal 2H

• Poor connection of ECT sensor or PCM connectors

• PCM malfunction

ON-BOARD DIAGNOSTIC 

F–97

F

Diagnostic procedure

End Of Sie

STEP

INSPECTION

ACTION

1

PERFORM DTC CONFIRMATION PROCEDURE

• Perform DTC CONFIRMATION PROCEDURE.

(See 

F–66 DTC CONFIRMATION 

PROCEDURE

.)

• Is same DTC present?

Yes Go to next step.

No

Intermittent concern exists. Go to INTERMITTENT 
CONCERN TROUBLESHOOTING procedure.
(See 

F–227 INTERMITTENT CONCERN 

TROUBLESHOOTING

.)

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?

Yes Repair or replace terminal, then go to Step 8.

No

Go to next step.

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?

Yes Replace ECT sensor, then go to Step 8.

No

Go to next step.

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+?

Yes Repair or replace harness for short to power, then go to 

Step 8.

No

Go to next step.

5

INSPECT POOR CONNECTION OF PCM 
CONNECTOR

• Disconnect PCM connector.

• Inspect for poor connection (damaged, pulled-

out pins, corrosion, etc.).

• Are there any malfunction?

Yes Repair or replace terminal, then go to Step 8.

No

Go to next step.

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?

Yes Go to next step.

No

Repair or replace harness for open, then go to Step 8.

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?

Yes Go to next step.

No

Repair or replace harness for open, then go to next step.

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 SELF-TEST

.)

• Is same DTC present?

Yes Replace PCM, then go to next step.

(See 

F–43 PCM REMOVAL/INSTALLATION

.)

No

Go to next step.

9

VERIFY AFTER REPAIR PROCEDURE

• Perform “After Repair Procedure”.

(See 

F–66 AFTER REPAIR PROCEDURE

.)

• Is there any DTC present?

Yes Go to applicable DTC troubleshooting.

(See 

F–67 DTC TABLE

.)

No

Troubleshooting completed.