P0606

DTC P0606: Engine Control Module Main Processor Malfunction

Engine Control Module Main Processor Malfunction Circuit

- Refer to Inspection Procedure 22 - Power Supply System and Ignition Switch-IG System Inspection Procedure 23 .

CIRCUIT OPERATION

- Refer to Inspection Procedure 22 - Power Supply System and Ignition Switch-IG System Inspection Procedure 23 .

TECHNICAL DESCRIPTION

- Throttle actuator control processor checks the ECM for abnormal conditions.

DESCRIPTIONS OF MONITOR METHODS

No watch dog pulse is detected.

MONITOR EXECUTION

Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)

- Not applicable
Sensor (The sensor below is determined to be normal)

- Not applicable

DTC SET CONDITIONS

Check Condition

- Ignition switch is "ON" position.
Judgement Criterion

- No surveillance pulse signals should be input for 0.5 second.

FAIL-SAFE AND BACKUP FUNCTION

- Throttle opening degree position is in default position.

OBD-II DRIVE CYCLE PATTERN

None.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)

- MFI relay failed.
- Shorted MFI relay circuit or connector damage.
- Open or shorted ignition switch-IG circuit, harness damage or connector damage.
- ECM failed.

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Check the battery.

Battery Test.

Q. Are there any abnormalities?

YES Replace the battery. Then go to Step 11.
NO Go to Step 2.
STEP 2. Check harness connector B-10 at ECM for damage.

Q. Is the harness connector in good condition?

YES Go to Step 3.
NO Repair or replace it. Harness Connector Inspection.
Then go to Step 11.
STEP 3. Measure the ignition switch-IG signal voltage at ECM harness side connector B-10.

(1)Disconnect the connector B-10 and measure at the harness side.

(2)Turn the ignition switch to the "ON" position.

(3)Measure the voltage between terminal No. 92 and ground.

- Voltage should be battery positive voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is battery positive voltage (approximately 12 volts) present?

YES Go to Step 5.

NO Go to Step 4.

STEP 4. Check harness connector C-304 at ETACS-ECU for damage.

Q. Is the harness connector in good condition?

YES Check harness connector C-50 at intermediate connector for damage, and repair or replace as required. Harness Connector Inspection.
If intermediate connector is in good condition, repair harness wire between ETACS-ECU connector C-304 (terminal No. 10) and ECM connector B-10 (terminal No. 92) because of open circuit or short circuit to ground. Then go to Step 11.
NO Repair or replace it. Harness Connector Inspection.
Then go to Step 11.
STEP 5. Check harness connector C-304 at ETACS-ECU for damage.

Q. Is the harness connector in good condition?

YES Go to Step 6.
NO Repair or replace it. Harness Connector Inspection.
Then go to Step 11.
STEP 6. Check for harness damage between ETACS-ECU connector C-304
(terminal No. 10) and ECM connector B-10 (terminal No. 92).

NOTE:
Check harness after checking intermediate connector C-50. If intermediate connector is damaged, repair or replace it. Harness Connector Inspection.
Then check that the malfunction is eliminated.

Q. Is the harness wire in good condition?

YES Go to Step 7.
NO Repair it. Then go to Step 11.
STEP 7. Check harness connector A-34X at MFI relay for damage.

Q. Is the harness connector in good condition?

YES Go to Step 8.
NO Repair or replace it. Harness Connector Inspection.
Then go to Step 11.
STEP 8. Check the MFI relay.

(1)Remove the MFI relay.

(2)Check for continuity between the MFI relay terminals No. 1 and No. 3.

- There should be continuity.

(3)Use jumper wires to connect MFI relay terminal No. 3 to the positive battery terminal and terminal No. 1 to the negative battery terminal.
(4)Check for continuity between the MFI relay terminals No. 4 and No. 2 while connecting and disconnecting the jumper wire at the negative battery terminal.

- Continuity (2 ohms or less)[ Negative battery terminal connected]
- Should be open loop[ Negative battery terminal disconnected]
(5)Install the MFI relay.

Q. Is the measured resistance within the specified range?

YES Go to Step 9.

NO Replace the MFI relay. Then go to Step 11.

STEP 9. Check for short circuit to ground between MFI relay connector A-34X (terminal No. 1) and ECM connector B-10 (terminal No. 73).

Q. Is the harness wire in good condition?

YES Go to Step 10.
NO Repair it. Then go to Step 11.
STEP 10. Using scan tool MB991958, read the diagnostic trouble code
(DTC).

CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)After the DTC has been deleted, read the DTC again.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is DTC P0606 set?

YES Replace the ECM (Refer to, Removal and Installation Removal and Replacement).
Then go to Step 11.

NO It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.

STEP 11. Using scan tool MB991958, read the diagnostic trouble code
(DTC).