Mitsubishi Galant (2004+). Manual - part 290

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-351

.

TECHNICAL DESCRIPTION (COMMENT)
If one of the headlights does not illuminate, a head-
light bulb may be defective.

.

TROUBLESHOOTING HINTS

• The headlight bulb may be defective

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

.

DIAGNOSIS

Required Special Tool:

• MB991223: Harness Set

STEP 1. Check the headlight operation.
Q: Which of the headlights does not illuminate?

LH (low and high beam) : Go to Step 2.
RH (low and high beam) : Go to Step 5.
LH (only low-beam) : Go to Step 8.
RH (only low-beam) : Go to Step 11.
LH (only high beam) : Go to Step 14.
RH (only high beam) : Go to Step 17.
Low beam only (both RH and LH) : Refer to Inspection 

Procedure H-2 "The headlights (low-beam) do not 
illuminate normally 

P.54B-313

."

High beam only (both RH and LH) : Refer to Inspection 

Procedure H-3 "The headlights (high-beam) do not 
illuminate normally 

P.54B-318

."

High beam indicator light : Refer to Inspection Procedure 

H-8 "The high-beam indicator light does not illuminate 

P.54B-369

."

STEP 2. Check headlight (LH) connector A-19 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.

Q: Is headlight (LH) connector A-19 in good condition?

YES : Go to Step 3.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Check that the headlights illuminate 

normally.

AC305210

A-19 (GR)

HARNESS SIDE

CONNECTOR: A-19

AM

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-352

STEP 3. Check headlight (LH) bulb.
(1) Remove the headlight (LH) bulb.
(2) Verify that the headlight (LH) bulb is not damaged or burned 

out.

Q: Is headlight (LH) bulb normal?

YES : Go to Step 4.
NO :  Replace the headlight (LH) bulb. Verify that the 

headlights illuminate normally.

STEP 4. Check the wiring harness between headlight (LH) 
connector A-19 (terminal 2) and ground.

Q: Is the wiring harness between headlight (LH) connector 

A-19 (terminal 2) and ground in good condition?
YES : No action is necessary and testing is complete.
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. Verify that 
the headlights illuminate normally.

STEP 5. Check headlight (RH) connector A-33 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.

Q: Is headlight (RH) connector A-33 in good condition?

YES : Go to Step 6.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Check that the headlights illuminate 

normally.

STEP 6. Check the headlight (RH) bulb.
(1) Remove the headlight (RH) bulb.
(2) Verify that the headlight (RH) bulb is not damaged or 

burned out.

Q: Is headlight (RH) bulb normal?

YES : Go to Step 7.
NO :  Replace the headlight (RH) bulb. Verify that the 

headlights illuminate normally.

AC305210

A-19 (GR)

HARNESS SIDE

CONNECTOR: A-19

AM

AC305206AM

CONNECTOR: A-33

A-33(GR)

HARNESS SIDE

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-353

STEP 7. Check the wiring harness between headlight (RH) 
connector A-33 (terminal 2) and ground.

Q: Is the wiring harness between headlight (RH) connector 

A-33 (terminal 2) and ground in good condition?
YES : No action is necessary and testing is complete.
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. Verify that 
the headlights illuminate normally.

STEP 8. Check headlight (LH) connector A-19 and 
front-ECU connector A-11X for loose, corroded or 
damaged terminals, or terminals pushed back in the 
connector.

Q: Are headlight (LH) connector A-19 and front-ECU 

connector A-11X in good condition?
YES : Go to Step 9.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Check that the headlights illuminate 

normally.

STEP 9. Check headlight (LH) bulb.
(1) Remove the headlight (LH) bulb.
(2) Verify that the headlight (LH) bulb is not damaged or burned 

out.

Q: Is headlight (LH) bulb normal?

YES : Go to Step 10.
NO :  Replace the headlight (LH) bulb. Verify that the 

headlights illuminate normally.

AC305206AM

CONNECTOR: A-33

A-33(GR)

HARNESS SIDE

AC305977AH

CONNECTOR: A-11X

RELAY BOX SIDE 

AC305210

A-19 (GR)

HARNESS SIDE

CONNECTOR: A-19

AM

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-354

STEP 10. Check the wiring harness between headlight (LH) 
connector A-19 (terminal 1) and front-ECU connector 
A-11X (terminal 6).

Q: Is the wiring harness between headlight (LH) connector 

A-19 (terminal 1) and front-ECU connector A-11X 
(terminal 6) in good condition?
YES : No action is necessary and testing is complete.
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. Verify that 
the headlights illuminate normally.

STEP 11. Check headlight (RH) connector A-33 and 
front-ECU connector A-11X for loose, corroded or 
damaged terminals, or terminals pushed back in the 
connector.

Q: Are headlight (RH) connector A-33 and front-ECU 

connector A-11X in good condition?
YES : Go to Step 12.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Check that the headlights illuminate 

normally.

AC305977AH

CONNECTOR: A-11X

RELAY BOX SIDE 

AC305210

A-19 (GR)

HARNESS SIDE

CONNECTOR: A-19

AM

AC305977AH

CONNECTOR: A-11X

RELAY BOX SIDE 

AC305206AM

CONNECTOR: A-33

A-33(GR)

HARNESS SIDE