Inspection Procedure 9: ETACS-ECU does not receive any signal from the liftgate switch. < LANCER SPORTBACK >: Diagnosis

Required Special Tools:

MB991223: Harness Set
MB992006: Extra Fine Probe

STEP 1. Check liftgate switch connector F-37 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is liftgate switch connector F-37 in good condition?
1. YES: Go to Step 2.
2. NO: Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Check that the input signal of liftgate switch is normal.

STEP 2. Check the liftgate switch.

Remove the liftgate switch. Then check the continuity between the switch terminals and the switch body.

Switch position	Tester connection	Specified condition
Released	1 - switch body	Continuity exists (2 ohms or less)
Pressed	1 - switch body	Open circuit

Q: Is the liftgate switch in good condition?

YES: Go to Step 3.
NO: Replace the liftgate switch. Check that the input signal of liftgate switch is normal.

STEP 3. Measure at the lower metal part of the liftgate switch in order to check the ground circuit to the liftgate switch.
NOTE: Check that the liftgate switch is grounded to the vehicle body by means of its mounting screw.

Remove the cap, and measure the resistance value between the lower metal part and ground.
- The resistance should equal 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
1. YES: Go to Step 4.
2. NO: Check the fit of the switch, and repair if necessary.
  Check that the input signal of liftgate switch is normal.
STEP 4. Check the ground circuit to the liftgate switch connector. Measure the resistance at liftgate switch connector F-37.
1. Disconnect liftgate switch connector F-37 and measure the resistance available at the wiring harness side of the connector.
2. Measure the resistance value between terminal 1 and ground.
  - The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
1. YES: Go to Step 6.
2. NO: Go to Step 5.
  
  Fig 1: Measuring Resistance At Liftgate Switch Connector F-37
  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 5. Check the wiring harness between liftgate switch connector F-37 (terminal 1) and ground.
Check the ground wires for open circuit.

Q: Is the wiring harness between liftgate switch connector F-37 (terminal 1) and ground in good condition?
1. YES: No action is necessary and testing is complete.
2. 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. Check that the input signal of key reminder switch is normal.
STEP 6. Check ETACS-ECU connector C-313 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-313 in good condition?
1. YES: Go to Step 7.
2. NO: Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Check that the input signal of liftgate switch is normal.
STEP 7. Check the wiring harness between liftgate switch connector F-37 (terminal 2) and ETACS-ECU connector C-313 (terminal 5).
Check the input lines for open circuit and short circuit.

NOTE: Also check intermediate connectors D-15 and F-30 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector D-15 or F-30 is damaged, repair or replace the connector as described in , HARNESS CONNECTOR INSPECTION .

Q: Is the wiring harness between liftgate switch connector F-37 (terminal 2) and ETACS-ECU connector C-313 (terminal 5) in good condition?
1. YES: Replace the ETACS-ECU. Check that the input signal of liftgate switch is normal.
2. 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. Check that the input signal of liftgate switch is normal.