Mitsubishi Lancer Evolution VI. Manual - part 65

ABS  – 

Troubleshooting

35B-10

<EVOLUTION-IV>

Code No.16 ABS-ECU power supply system (abnormal
voltage drop or rise)

Probable cause

This code is output if the ABS-ECU or valve relay power supply voltage drops below
or rises above the rated values.
The valve relay power supply voltage is detected based on the voltage in the valve
relay monitor line.

D

Malfunction of battery

D

Malfunction of wiring harness or connector

D

Malfunction of valve relay

D

Malfunction of ABS-ECU

Caution
If system voltage drops or rises during inspection, this code will be output as well, making it
impossible to obtain correct diagnostic results.
Before carrying out the following inspection, check the battery level, and refill it if necessary.

OK

Replace ABS-ECU.

OK

Replace the ABS-ECU.

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between ignition switch and
ABS-ECU

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between general-purpose  fuse
No. 6 and valve relay

NG

Repair

OK

Check the harness wire for short
circuit, and repair if necessary.

D

Between valve relay and hydraulic
unit

D

Between valve relay and motor
relay

NG

Repair

OK

NG

Check the harness wire, and repair
if necessary.

D

Between valve relay and ABS-ECU

NG

Repair

OK

Check the trouble symptom.

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between valve relay and ABS-
ECU

OK

Measure at the ABS-ECU connector
B-25.

D

Connector connected

D

Ignition switch: ON

(1) Voltage between 42 and body

ground
OK: System voltage

(2) Voltage between 34 and body

ground
OK: System voltage

(1) NG

Check the following connectors:
A-76, B-25

NG

Repair

(2) NG

Check the following connectors:
A-76, B-25

NG

Repair

OK

Check the valve relay. 
(Refer to P.35B-39.)

NG

Replace

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between fusible link No. 8 and
valve relay

OK

Measure at the valve relay connector
A-76.

D

Disconnect the connector, and
measure at the harness side
connector.

D

Ignition switch: ON

(1) Voltage between 6 and body

ground
OK: System voltage

(2) Voltage between 2 and body

ground
OK: System voltage

(1) NG

Check the following connector:
A-76

NG

Repair

(2) NG

Check the following connector:
A-76

NG

Repair

Measure at the ABS-ECU connector
B-24.

D

Disconnect the connector, and
measure at the harness side
connector.

D

Start the engine.

D

Voltage between 26 and body
ground
OK: System voltage

NG

Check the following connectors:
B-24, B-52, B-74, B-76

NG

Repair

ABS  – 

Troubleshooting

35B-11

<EVOLUTION-V, VI>

Code No.16 ABS-ECU power supply system (abnormal
voltage drop or rise)

Probable cause

This code is output if the ABS-ECU or valve relay power supply voltage drops below
or rises above the rated values.
The valve relay power supply voltage is detected based on the voltage in the valve
relay monitor line.

D

Malfunction of battery

D

Malfunction of wiring harness or connector

D

Malfunction of valve relay

D

Malfunction of ABS-ECU

Caution
If system voltage drops or rises during inspection, this code will be output as well, making it
impossible to obtain correct diagnostic results.
Before carrying out the following inspection, check the battery level, and refill it if necessary.

OK

Replace ABS-ECU.

OK

Replace the ABS-ECU.

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between ignition switch and
ABS-ECU

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between general-purpose  fuse
No. 6 and valve relay

NG

Repair

OK

Check the harness wire for short
circuit, and repair if necessary.

D

Between valve relay and hydraulic
unit

D

Between valve relay and motor
relay

NG

Repair

OK

NG

Check the harness wire, and repair
if necessary.

D

Between valve relay and ABS-ECU

NG

Repair

OK

Check the trouble symptom.

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between valve relay and ABS-
ECU

OK

Measure at the ABS-ECU connector
B-25.

D

Connector connected

D

Ignition switch: ON

(1) Voltage between 37 and body

ground
OK: System voltage

(2) Voltage between 48 and body

ground
OK: System voltage

(1) NG

Check the following connectors:
A-76, B-25

NG

Repair

(2) NG

Check the following connectors:
A-76, B-25

NG

Repair

OK

Check the valve relay. 
(Refer to P.35B-39.)

NG

Replace

OK

Check the trouble symptom.

NG

Check the harness wire, and repair
if necessary.

D

Between fusible link No. 8 and
valve relay

OK

Measure at the valve relay connector
A-76.

D

Disconnect the connector, and
measure at the harness side
connector.

D

Ignition switch: ON

(1) Voltage between 6 and body

ground
OK: System voltage

(2) Voltage between 2 and body

ground
OK: System voltage

(1) NG

Check the following connector:
A-76

NG

Repair

(2) NG

Check the following connector:
A-76

NG

Repair

Measure at the ABS-ECU connector
B-24.

D

Disconnect the connector, and
measure at the harness side
connector.

D

Start the engine.

D

Voltage between 13 and body
ground
OK: System voltage

NG

Check the following connectors:
B-24, B-52, B-74, B-76

NG

Repair

ABS  – 

Troubleshooting

35B-12

<EVOLUTION-IV>

Code No.27 AYC monitor system (defective AYC)

Probable cause

This code is output when the AYC monitor signal becomes faulty.

D

Defective AYC-ECU

D

Defective ABS-ECU

D

Defective harness or connector

OK

Replace the ABS-ECU.

OK

MUT-

II

 Data list

27 AYC signal
OK

OFF to be displayed when the
engine runs at idle with the
vehicle stationary.

NG

Replace AYC-ECU.

OK

Check the harness between ABS-ECU
and AYC-ECU.

NG

Repair

Check the following connectors:
B-25, B-96

NG

Repair

<EVOLUTION-IV>

Code No.32 Acceleration sensor circuit system

Probable cause

This code is output under either of the following conditions:

D

The output from the acceleration sensor becomes 0.5 V or less, or 4.5 V or more.

D

The acceleration sensor harness is open- or short-circuited.

D

Defective acceleration sensor

D

Defective harness or connector

D

Defective ABS-ECU

OK

Check the trouble symptom.

NG

Replace ABS-ECU.

OK

Check the trouble symptom.

NG

Check and repair the harness between
acceleration sensor and ABS-ECU.

OK

Check the following connector:
B-24

NG

Repair

OK

 Measure at B-24 ABS-ECU connector.

D

Disconnect the connector and
measure at the harness side.

D

Ignition switch: ON

D

Voltage across 17 and 18
OK: 2.4  – 2.6 V 

(horizontal position)

NG

Check the following connectors:
B-24, B-52, D-20

NG

Repair

Check the acceleration sensor. 
(Refer to P.35B-46.)

NG

Replace

ABS  – 

Troubleshooting

35B-13

<EVOLUTION-V, VI>

Code No.32 Acceleration sensor (longitudinal accelera-
tion) circuit system

Probable cause

This code is output under either of the following conditions:

D

The output from the acceleration sensor (longitudinal acceleration) becomes 0.5
V or less, or 4.5 V or more.

D

The acceleration sensor (longitudinal acceleration) harness is open- or
short-circuited.

D

Defective acceleration sensor (longitudinal accelera-
tion)

D

Defective harness or connector

D

Defective ABS-ECU

OK

Check the trouble symptom.

NG

Replace ABS-ECU.

OK

Check the trouble symptom.

NG

Check and repair the harness between
acceleration sensor (longitudinal
acceleration) and ABS-ECU.

OK

Check the trouble symptom.

NG

Check and repair the harness between
general-purpose fuse No. 6 and
acceleration sensor (longitudinal
acceleration).

OK

Replace ABS-ECU.

OK

Check the following connector:
B-24

NG

Repair

OK

 Measure at B-24 ABS-ECU connector.

D

Connect the connector.

D

Ignition switch: ON

D

Voltage across 4 and 17
OK: 2.4  – 2.6 V 

(horizontal position)

NG

Check the following connectors:
B-24, D-20, B-52

NG

Repair

NG

Check the harness between accelera-
tion sensor (longitudinal acceleration)
and ABS-ECU.

NG

Repair

OK

Check the trouble symptom.

OK

Check the acceleration sensor
(longitudinal acceleration). 
(Refer to P.35B-46.)

NG

Replace

(1) NG

Check the following connectors:
D-20, B-49, B-75

NG

Repair

Check the following connector:
D-20, B-49, B-75

NG

Repair

(2) NG

Measure at D-20 acceleration sensor
(longitudinal acceleration) connector.

D

Disconnect the connector and
measure at the harness side.

D

Ignition switch: ON

(1) Voltage across 1 and body ground

OK: System voltage

(2) Continuity across 3 and body

ground
OK: Conducting