Mitsubishi L200. Manual — part 298

TROUBLESHOOTING

AUTOMATIC TRANSMISSION

23A-99

Inspection Procedure 18: Shift Switch Assembly System <5A/T>

IGNITION
SWITCH (IG1)

A/T-ECU

SHIFT
SWITCH
ASSEMBLY

SELECT
SWITCH

SHIFT
SWITCH

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White Y : Yellow SB : Sky blue
BR : Brown O : Orange GR : Grey R : Red P : Pink V : Violet PU : Purple SI : Silver

INHIBITOR
SWITCH

Shift Switch System Circuit

AC903920

<LHD>
<RHD>

<LHD>
<RHD>

<LHD>
<RHD>

<LHD>
<RHD>

AC510056AD

Harness side

B-10 (B)

Connector: B-10

AC510056AG

B-14 (B)

Connector: B-14

Harness side

AC510057

Harness side

A/T-ECU

C-20

AC

Connector: C-20

A/T-ECU

<RHD>

<LHD>

AC509930AG

Connector: C-34 <RHD>

C-34

Harness side

AC509613AG

Connector: C-52 <LHD>

C-52

Harness side

AC903865AM

Connector: C-172 <RHD>

C-172

AC903853

BF

Connector: C-172 <LHD>

C-172

AC509934

Connectors: C-208 <LHD>

Junction block (Front view)

C-208

AH

Harness side

TROUBLESHOOTING

AUTOMATIC TRANSMISSION

23A-100

OPERATION
The shift switch assembly detects the shift range
(sport mode) which the driver has selected, and
sends the information to the A/T-ECU.

COMMENTS ON TROUBLE SYMPTOM
The cause is probably a malfunction of the shift
switch and A/T-ECU.

TROUBLESHOOTING

AUTOMATIC TRANSMISSION

23A-101

PROBABLE CAUSES

• Malfunction of shift switch assembly

• Damaged harness wires and connectors

• Malfunction of the A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code
Either of diagnosis codes P1770 or P1771 is set,
inhibitor switch is defective.

Q: Are diagnosis codes P1770 or P1771 output?

YES <diagnosis code P1770 is set> :

Refer to

diagnosis code P1770: Inhibitor switch
system

P.23A-49

.

YES <diagnosis code P1771 is set> :

Refer to

diagnosis code P1771: Inhibitor switch
system

P.23A-52

.

NO :

Go to Step 2.

STEP 2. M.U.T.-III data list

• Item 27: Select switch

• Item 28: Shift switch (Up)

• Item 29: Shift switch (Down)

(Refer to data list reference table

P.23A-103

).

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Cope with Intermittent

Malfunction ).

NO <"NG" for all items> :

Go to Step 3.

NO <"NG" for items 28 and 29> :

Go to Step 5.

NO <"NG" for item 27> :

Go to Step 10.

NO <"NG" for item 28> :

Go to Step 17.

NO <"NG" for item 29> :

Go to Step 20.

STEP 3. Connectors check: C-172 shift switch
assembly connector, C-20 A/T-ECU connector.
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the defective connector.

STEP 4. M.U.T.-III data list

• Item 27: Select switch

• Item 28: Shift switch (Up)

• Item 29: Shift switch (Down)

Check the above data list (Refer to data list reference
table

P.23A-103

).

Q: Is the check result normal?

YES :

Intermittent malfunction (Refer to GROUP

00

− How to Cope with Intermittent

Malfunction ).

NO :

Replace the A/T-ECU.

STEP 5. Check the shift switch assembly.
Refer to

P.23A-134

.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Replace the shift lever assembly.

STEP 6. Connector check: C-172 shift switch
assembly connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Repair the defective connector.

STEP 7. Measure the voltage at shift switch
assembly connector C-172.
(1) Disconnect the connector, and measure the

voltage between terminal 3 and earth at the
wiring harness side.

(2) Ignition switch: ON

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Go to Step 8.

STEP 8. Connectors check: C-208 J/B connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 9.

NO :

Repair the defective connector.

STEP 9. Check the harness between shift switch
assembly connector C-172 terminal No.3 and J/B
connector C-208 terminal No.2.
Check the power supply line for short or open circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.

STEP 10. Check the shift switch assembly.
Refer to

P.23A-134

.

Q: Is the check result normal?

YES :

Go to Step 11.

NO :

Replace the shift lever assembly.

TROUBLESHOOTING

AUTOMATIC TRANSMISSION

23A-102

STEP 11. Connector check: C-172 shift switch
assembly connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 12.

NO :

Repair the defective connector.

STEP 12. Measure the voltage at shift switch
assembly connector C-172
(1) Disconnect the connector, and measure the

voltage between terminal 1 and earth at the
wiring harness side.

(2) Selector lever position: D
(3) Ignition switch: ON

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 13.

NO :

Go to Step 15.

STEP 13. Connectors check: C-20 A/T-ECU
connector, C-34 <RHD> or C-52 <LHD>
intermediate connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 14.

NO :

Repair the defective connector.

STEP 14. Check the harness between shift switch
assembly connector C-172 terminal No.4 and A/T-
ECU connector C-20 terminal No.57.
Check the output line for short-circuited or open cir-
cuit.

Q: Is the check result normal?

YES :

Go to Step 15.

NO :

Repair the wiring harness.

STEP 15. Connector check: B-10, C-34 <RHD> or
C-52 <LHD> intermediate connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 16.

NO :

Repair the defective connector.

STEP 16. Check the harness between shift switch
assembly connector C-172 terminal No.1 and
inhibitor switch connector B-14 terminal No.3.
Check the power supply line for short or open circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.

STEP 17. Check the shift switch assembly.
Refer to

P.23A-134

.

Q: Is the check result normal?

YES :

Go to Step 18.

NO :

Replace the shift switch assembly.

STEP 18. Connectors check: C-172 shift switch
assembly connector, C-20 A/T-ECU connector
and C-34 <RHD> or C-52 <LHD> intermediate
connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 19.

NO :

Repair the defective connector.

STEP 19. Check the harness between shift switch
assembly connector C-172 terminal No.6 and A/T-
ECU connector C-20 terminal No.58.
Check the output line for short-circuited or open cir-
cuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.

STEP 20. Check the shift switch assembly.
Refer to

P.23A-134

.

Q: Is the check result normal?

YES :

Go to Step 21.

NO :

Replace the shift switch assembly.

STEP 21. Connectors check: C-172 shift switch
assembly connector, C-20 A/T-ECU connector
and C-34 <RHD> or C-52 <LHD> intermediate
connector
Check for the contact with terminals.

Q: Is the check result normal?

YES :

Go to Step 22.

NO :

Repair the defective connector.

STEP 22. Check the harness between shift switch
assembly connector C-172 terminal No.5 and A/T-
ECU connector C-20 terminal No.68.
Check the output line for short-circuited or open cir-
cuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.