Mitsubishi Galant. Manual — part 668

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-67

DIAGNOSIS

Required Special Tools:

•

MB991502: Scan Tool (MUT-II)

•

MB991529: Diagnostic Trouble Code Check Harness

STEP 1. Check method of the input signal

Q: Which is to be used, the scan tool or the voltmeter to

check the input signal?
Scan tool MB991502 : Go to Step 2.
Voltmeter : Go to Step 3.

STEP 2. Check the input signal (by using scan tool
MB991502).
Check the input signals from the following switches:

•

Ignition switch (IG1)

•

Driver's and front passenger's door switch

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1)Connect scan tool MB991502 to the data link connector.
(2)Check that the tone alarm of scan tool MB991502 sounds

when the input signal enters.

Q: Does the tone alarm of scan tool MB991502 sound when

the input signal enters?
YES : Go to Step 4.
NO : Check the relevant input circuit. Refer to

P.54B-9

.

STEP 3. Check the input signal (by using a voltmeter).
Check the input signals from the following switches:

•

Ignition switch (IG1)

•

Driver's and front passenger's door switch

(1)Use special tool MB991529 to connect a voltmeter between

ground terminal 4 or 5 and ETACS-ECU terminal 9 of the
data link connector.

(2)Check that the voltmeter indicator deflects once when the

input signal enters.

Q: Does the voltmeter indicator deflect?

YES : Go to Step 4.
NO : Check the relevant input circuit. Refer to

P.54B-9

.

AC003081 AB

16 PIN

MB991502

AC003083

16 PIN

AB

ETACS-ECU
TERMINAL

GROUNDED TERMINAL

MB991529

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-68

STEP 4. Replacement of ECU.
(1)Replace the front-ECU.
(2)The power window timer function should work normally.

Q: Is the power window timer function working normally?

YES : Replace the ETACS-ECU. The power window timer

function should work normally.

NO : There is no action to taken.

Inspection Procedure E-1: Keyless entry system: Keyless entry system does not operate.

CIRCUIT OPERATION
Receiver within the ETACS-ECU receives the lock/
unlock signal from the transmitter.

TECHNICAL DESCRIPTION (COMMENT)
The cause may be a malfunction of the receiver and
transmitter communication system.

TROUBLESHOOTING HINTS

•

Malfunction of the ETACS-ECU

•

Malfunction of the transmitter

DIAGNOSIS

Required Special Tools:

•

MB991502: Scan Tool (MUT-II)

•

MB991529: Diagnostic Trouble Code Check Harness

STEP 1. Check the central door locking system operation.

Q: Does the central door locking system work normally?

YES : Go to Step 2 <when using scan tool MB991502> or 3

<when using a voltmeter>.

NO : Solve the problem first. Refer to

P.54B-40

.

AC004205

Receiver and Transmitter Communication System

SWS DIAGNOSIS

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-69

STEP 2. Check the input signal (by using scan tool
MB991502).
Check the input signals from the transmitter switches.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1)Connect scan tool MB991502 to the data link connector.
(2)Check that the tone alarm of scan tool MB991502 sounds

when the input signal enters.

Q: Does the tone alarm of scan tool MB991502 sound when

the input signal enters?
YES : Replace the ETACS-ECU. All the doors should be

locked or unlocked by using the transmitter.

NO : Check the transmitter input circuit. Refer to Inspection

Procedure N-17 (

P.54B-265

).

STEP 3. Check the input signal (by using a voltmeter).
Check the input signals from the transmitter switches.
(1)Use special tool MB991529 to connect a voltmeter between

ground terminal 4 or 5 and ETACS-ECU terminal 9 of the
data link connector.

(2)Check that the voltmeter indicator deflects once when the

input signal enters.

Q: Does the voltmeter indicator deflect?

YES : Replace the ETACS-ECU. All the doors should be

locked or unlocked by using the transmitter.

NO : Check the transmitter input circuit. Refer to Inspection

Procedure N-17 (

P.54B-265

).

AC003081 AB

16 PIN

MB991502

AC003083

16 PIN

AB

ETACS-ECU
TERMINAL

GROUNDED TERMINAL

MB991529

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-70

Inspection Procedure E-2: Keyless entry system: The dome light, the hazard warning lights and the
horn do not operate through the answerback function.

Horn Circuit <2000 models without theft-alarm system>

AC004206