Mitsubishi Eclipse / Eclipse Spyder (2000-2002). Service and repair manual — part 459

AUTOMATIC TRANSAXLE DIAGNOSIS

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AUTOMATIC TRANSAXLE

23A-128

CIRCUIT OPERATION

•

Battery positive voltage is supplied to the
stoplight switch (terminal 2).

•

When the brake pedal is depressed, battery
positive voltage is applied to the PCM (terminal
123). The PCM judges that the brake pedal is
depressed and the stoplight switch is on when
battery positive voltage is sensed at the PCM
(terminal 123).

DTC SET CONDITIONS
If the stoplight switch is on for five minutes or more
while driving 50 km/h (31 mph), it is judged there is a
short circuit in the stoplight switch and diagnostic
trouble code number "26" is output.

TROUBLESHOOTING HINTS (The most likely

causes for this code to be set:)

•

Malfunction of the stoplight switch circuit

•

Damaged harness, connector

•

Malfunction of the PCM

DIAGNOSIS

Required Special Tool:
MB991502: Scan Tool (MUT-II)

STEP 1. Check the brake pedal height.
Refer to GROUP 35A, On-vehicle Service - Brake Pedal Check
and Adjustment

P.35A-18

.

Q: Is the height adjusted properly?

YES : Go to Step 2.
NO : Adjust it.

AC001657

CONNECTOR: C-61 <2.4L ENGINE> OR
C-63 <3.0L ENGINE>

PCM

AN

AC001748 AF

CONNECTOR BLOCK (LH)

CONNECTOR: C-89

AC001691

CONNECTOR: C-107

JUNCTION BLOCK
(FRONT VIEW)

AO

AC001896

CONNECTOR: C-110

JUNCTION BLOCK
(REAR VIEW)

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AUTOMATIC TRANSAXLE DIAGNOSIS

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STEP 2. Using scan tool MB991502, check data list item 26:
Stoplight Switch.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to "ON" position.
(3) Set scan tool MB991502 to data reading mode for item 26,

Stoplight Switch.

•

When the brake pedal is depressed, the display should
be "ON."

•

When the brake pedal is not depressed, the display
should be "OFF."

(4) Turn the ignition switch to "LOCK" (OFF) position.

Q: Is the switch operating properly?

YES : This malfunction may be intermittent. Refer to

GROUP 00, How to Use Troubleshooting/Inspection
Service Points

−

How to Cope with Intermittent

Malfunction

P.00-6

.

NO : Go to Step 3.

STEP 3. Check the stoplight switch as single part.
Refer to GROUP 35A, On-vehicle Service

−

Stoplight Switch

Check

P.35A-19

.

Q: Is the switch normal?

YES : Go to Step 4.
NO : Replace the stoplight switch. Refer to GROUP 35A,

Stoplight Switch Check

P.35A-19

.

STEP 4. Check connector C-03 at stoplight switch for
damage.
Q: Is the connector in good condition?

YES : Go to Step 5.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

.

AC001252

MB991502

16 PIN

AB

ACX02208

BRAKE PEDAL

STOPLIGHT
SWITCH

AD

AC001729

CONNECTOR: C-03

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AUTOMATIC TRANSAXLE DIAGNOSIS

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STEP 5. Check the switch output voltage at PCM
connector C-61 <2.4L Engine> or C-63 <3.0L Engine> by
backprobing.
(1) Do not disconnect connector C-61 <2.4L Engine> or C-63

<3.0L Engine>.

(2) Measure the voltage between terminal 123 and ground by

backprobing.

•

When the brake pedal is depressed, voltage should be
battery positive voltage.

•

When the brake pedal is not depressed, voltage should
be less than 1.0 volt.

Q: Is the voltage normal?

YES : Go to Step 8.
NO : Go to Step 6.

AC001657

CONNECTOR: C-61 <2.4L ENGINE> OR
C-63 <3.0L ENGINE>

PCM

AN

AC001812

C-61 <2.4L ENGINE> OR
C-63 <3.0L ENGINE>
CONNECTOR HARNESS
SIDE VIEW

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AUTOMATIC TRANSAXLE DIAGNOSIS

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STEP 6. Check connectors C-61 <2.4L Engine> or C-63
<3.0L Engine> at PCM and C-89, C-28 at intermediate
connector for damage.
Q: Are the connectors in good condition?

YES : Go to Step 7.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

.

AC001657

CONNECTOR: C-61 <2.4L ENGINE> OR
C-63 <3.0L ENGINE>

PCM

AN

AC001741 AJ

CONNECTOR: C-28

AC001748 AF

CONNECTOR BLOCK (LH)

CONNECTOR: C-89