Inspection Procedure O-5

ETACS-ECU does not Receive "R" Position Signal from the Transmission Range Switch .

Transmission Range Switch Input Circuit Part 1:

Transmission Range Switch Input Circuit Part 2:

CIRCUIT OPERATION
The ETACS-ECU operates the rear wiper according to signal from the transmission range switch.

TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the rear wiper does not operate consecutively twice when the selector lever is moved to the "R" position with the rear wiper on. If the signal is not normal, the transmission range switch or the ETACS-ECU may be defective.

NOTE: The transmission range switch is shared with the automatic transmission control system. If this problem is not solved, carry out the troubleshooting regarding the automatic transmission control system. Refer to A/T Diagnosis.

TROUBLESHOOTING HINTS
- The transmission range switch may be defective
- The ETACS-ECU may be defective
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector

DIAGNOSIS

Required Special Tool:
- MB991223: Test Harness Set

STEP 1. Check transmission range switch connector B-41 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is transmission range switch connector B-41 in good condition?

YES: Go to Step 2.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.

STEP 2. Check the transmission range switch.
Disconnect transmission range switch connector B-41. Then check continuity between the switch terminals.

Q: Is the transmission range switch in good condition?

YES: Go to Step 3.

NO: Replace the transmission range switch. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.

STEP 3. Check the ignition switch (IG1) line of the power supply circuit to the transmission range switch. Measure the voltage at transmission range switch connector B-41.










1. Disconnect transmission range switch connector B-41 and measure the voltage available at the wiring harness side of the connector.
2. Turn the ignition switch to the "ON" position.




3. Measure the voltage between terminal 8 and ground.
- The voltage should equal approximately 12 volts (battery positive voltage).

Q: Is the measured voltage approximately 12 volts (battery positive voltage)?

YES: Go to Step 5.

NO: Go to Step 4.
















STEP 4. Check the wiring harness between transmission range switch connector B-41 (terminal 8) and the ignition switch (IG1).

NOTE: Also check junction block connectors C-111, C-112 and intermediate connector C-28 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If junction block connectors C-111, C-112 or intermediate connector C-28 are damaged, Repair or replace the damaged component(s) as described in Harness Connector Inspection.

Q: Is the wiring harness between transmission range switch connector B-41 (terminal 8) and the ignition switch (IG1) in good condition?

YES: No action is necessary and testing is complete.

NO: The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.




STEP 5. Check ETACS-ECU connector C-117 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connector C-117 in good condition?

YES: Go to Step 6.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.
















STEP 6. Check the wiring harness between transmission range switch connector B-41 (terminal 7) and ETACS-ECU connector C-117 (terminal 39).

NOTE: Also check intermediate connector C-28 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-28 is damaged, Repair or replace the damaged component(s) as described in Harness Connector Inspection.

Q: Is the wiring harness between transmission range switch connector B-41 (terminal 7) and ETACS-ECU connector C-117 (terminal 39) in good condition?

YES: Replace the ETACS-ECU. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.

NO: The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.