Inspection Procedure 19: The transmission range switch signal is not received.
caution
Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
TECHNICAL DESCRIPTION (COMMENT)
If there is an error to the transmission range switch input signal, the transmission range switch signal is no longer output to the communication line.
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 Tools:
MB991223: Harness Set
MB992006: Extra Fine Probe
STEP 1. Check the transmission range switch.
Check the continuity of the transmission range switch (Refer to GROUP 23A - On-vehicle Service - Transmission Range Switch Continuity Check ).
Is the check result normal?
Go to Step 2.
Replace the transmission range switch.
STEP 2. Voltage measurement at ETACS-ECU connector (BLP- terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Move the selector lever to the "R" (reverse) position.
(4) Check the voltage between the ETACS-ECU connector (BLP- terminal) and body ground.
OK: The voltage should measure approximately 12 volts (battery positive voltage)
Is the check result normal?
Go to Step 6.
Go to Step 3.
STEP 3. Check of open circuit in BLP- line between ETACS-ECU connector and transmission range switch connector.
Is the check result normal?
Go to Step 4.
Repair the connector(s) or wiring harness.
STEP 4. Check of open circuit in +B1 line between fusible link and ETACS-ECU connector.
Is the check result normal?
Go to Step 5.
Repair the connector(s) or wiring harness.
STEP 5. Check of open circuit in BLP+ line between ETACS-ECU connector and transmission range switch connector.
Is the check result normal?
Go to Step 6.
Repair the connector(s) or wiring harness.
STEP 6. Using scan tool (M.U.T.-IIISE), check data list.
Check the ETACS-ECU data list.
(1)
caution
To prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).
Connect scan tool (M.U.T.-IIISE). Refer to "How to connect Scan Tool (M.U.T.-IIISE) ."
(2) Check the input signals from the transmission range switch.
Selector lever is in reverse position
Item No.
Item name
Normal condition
112
Backup light/Shift reveres switch
ON
Selector lever is not in reverse position
Item No.
Item name
Normal condition
112
Backup light/Shift reveres switch
OFF
OK: Normal condition is displayed.
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).