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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.
  • When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in Immobilizer System - How to Register Key ID .)
 
 
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 for continuity of the transmission range switch. (Refer to GROUP 23A - On-vehicle service, Transmission range switch continuity check <CVT> or Refer to GROUP 23C - On-vehicle service, Transmission range switch check <A/T>)
Is the check result normal?
Go to Step 2.
Replace the transmission range switch.
 
STEP 2. Voltage measurement at ETACS-ECU connector (BLP1 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 (BLP1 terminal) and 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 short to power supply, short to ground, and open circuit in BLP1 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 connector 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.-III), check data list.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III). Refer to "How to connect Scan Tool (M.U.T.-III) ."
(2) Check the input signals from the transmission range switch.
  • Selector is "R" (Reverse) position
 
Item No.Item nameNormal condition
289Backup light or shift reverse SWON
Item No.Item nameNormal condition
289Backup light or shift reverse SWON
  • Selector is not "R" (Reverse) position
 
Item No.Item nameNormal condition
289Backup light or shift reverse SWOFF
Item No.Item nameNormal condition
289Backup light or shift reverse SWOFF
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 ).
Replace the ETACS-ECU.