Inspection Procedure 3: The back-up lamp do not illuminate normally.
caution |
Whenever the ECU is replaced, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.
|
COMMENTS ON TROUBLE SYMPTOM
If both of the back-up lamp do not illuminate normally, the input signal circuit(s) or the inhibitor switch <CVT>, back-up lamp switch <M/T>, may be defective.
PROBABLE CAUSES
- Malfunction of the inhibitor switch <CVT> or buck-up lamp switch <M/T>
- Malfunction of bulbs
- Malfunction of the rear combination lamp assembly
- Damaged harness wires and connectors
|
STEP 1. Check the operation of the position lamps and the headlamps.
|
|
Check that the position lamps and the headlamps illuminate normally.
|
|
Q.
Is the check result normal?
|
|
Go to Step 2.
|
|
|
|
Check the position lamps and the headlamps (Refer to trouble symptom chart ).
|
|
|
|
STEP 2. Check the inhibitor switch <CVT> or back-up lamp switch <M/T>.
|
|
Check the continuity of the inhibitor switch <CVT> or the back-up lamp switch <M/T>.(GROUP 23A - On-vehicle Service, Inhibitor Switch Continuity Check <CVT>, GROUP 22B - Transmission, Transmission Inspection )
|
|
Q.
Is the check result normal?
|
|
Go to Step 3.
|
|
|
|
Replace the inhibitor switch <CVT> or back-up lamp switch <M/T>.
|
|
|
|
STEP 3. Voltage measurement at the inhibitor switch connector <CVT> or back-up lamp switch connector <M/T>.
|
|
(1)Remove the inhibitor switch connector <CVT> or back-up lamp switch connector <M/T>, and measure at the junction block side.
|
|
(2)Move the ignition switch to the ON position.
|
|
(3)Measure the voltage between the inhibitor switch connector <CVT> or back-up lamp switch connector <M/T> (power supply terminals) and body earth. OK: System voltage
|
|
Q.
Is the check result normal?
|
|
Go to Step 5.
|
|
|
|
Go to Step 4.
|
|
|
|
STEP 4. Check of open circuit in power supply line between the inhibitor switch connector <CVT> or back-up lamp switch connector <M/T> and the ignition switch (IG1).
|
|
Q.
Is the check result normal?
|
|
Go to Step 5.
|
|
|
|
Repair the connector(s) or wiring harness.
|
|
|
|
STEP 5. Check the bulb of the back-up lamp
|
|
Check the bulb of the defective lamp.
|
|
Q.
Is the check result normal?
|
|
Go to Step 6.
|
|
|
|
Replace the bulb of the defective lamp.
|
|
|
|
STEP 6. Resistance measurement at the rear combination lamp (back-up lamp) connector
|
|
(1)Disconnect the connector, and measure at the wiring harness side.
|
|
(2)Check the resistance between the lamp connector and body earth.
- Measure the resistance between the rear combination lamp (back-up lamp) connector (earth terminal) and the body earth.
OK: Continuity exists (2 Ω or less)
|
|
Q.
Is the check result normal?
|
|
Go to Step 8.
|
|
|
|
Go to Step 7.
|
|
|
|
STEP 7. Check of open circuit in body earth line between rear combination lamp (back-up lamp) connector and body earth.
|
|
Q.
Is the check result normal?
|
|
Go to Step 8.
|
|
|
|
Repair the connector(s) or wiring harness.
|
|
|
|
STEP 8. Check of open circuit in output line between the rear combination lamp (back-up lamp) connector and back-up lamp switch connector.
|
|
Q.
Is the check result normal?
|
|
Go to Step 9.
|
|
|
|
Repair the connector(s) or wiring harness.
|
|
|
|
STEP 9. Retest the system
|
|
Check that the back-up lamp illuminate normally.
|
|
Q.
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 rear combination lamp assembly.
|
|
|