Mitsubishi Lancer Evolution 8. Manual - part 114

SRS AIRBAGS – TROUBLESHOOTING

52B-21

If the Code No. above is output, then replace the SRS-ECU.

If the Code No. above is output, then replace the SRS-ECU with one which is compatible with a front passenger airbag.

Code No. 39 All airbags deployed system

Possible cause

This code is output after an operation in which all the airbags
have deployed. If this code is output before all the airbags
have deployed, then this indicates that there is an internal
malfunction in the SRS-ECU.

SRS-ECU fault

Code No. 46 Incorrect SRS-ECU installation

Possible cause

This code is output if an SRS-ECU compatible with driver
airbag only, is mistakenly installed in a vehicle fitted with front
passenger airbag.

Installation of incorrect SRS-ECU

(Checking the driver’s airbag module (squib))
MUT-II/III diagnosis code
• Detach the (–) terminal of the battery
• Detach the driver's airbag module connector C-207
• Connect the dummy resistor (MB991865) to the resistor

harness (MB 991866)

• Insert the probe of the resistor harness (MB991866) behind

the driver's airbag module connector C-207 of the clock
spring.
Caution
Do not insert the probe directly into the terminal from
the front side of the connector, as this may cause a
reduction in contact pressure.

• Connect the (–) terminal of the battery.
• After erasing the diagnosis code memory, reconfirm the

diagnosis code.

Is Code No.61 or No. 62 output?

(Checking the clock spring)
MUT-II/III diagnosis code
• Detach the (–) terminal of the battery
• Detach the clock spring connector (4-pin) C-204
• Connect the dummy resistor (MB991865) to the resistor

harness

• Insert the probe of the resistor harness (MB991866)

between terminals 3 and 4, behind clock spring connector
C-204 (harness side)
Caution
Do not insert the probe directly into the terminal from
the front side of the connector, as this may cause a
reduction in contact pressure.

• Connect the (–) terminal of the battery.
• After erasing the diagnosis code memory, reconfirm the

diagnosis code.

Is Code No.61 or No.62 output?

SRS AIRBAGS – TROUBLESHOOTING

52B-22

(Type 1)

Replace the clock spring

Replace the driver's airbag module (squib)

To next page

Code No. 61 Driver's airbag module (squib) system (shorted to power
supply)

Code No. 62 Driver's airbag module (squib) system (shorted to earth)

Possible cause

This code is output when the driver's airbag module (squib) circuit of the
SRS-ECU is shorted to the power supply (Code No. 61) or shorted to earth
(Code No. 62).

• Clock spring fault
• Harness or connector fault
• Shorting of driver's airbag module (squib)

harness to power supply (Code No. 61) or to
earth (Code No. 62)

• SRS-ECU fault

Dummy resistor
(MB991865)
resistance (3Ω)

Resistor harness
(MB991866)

C-207 Driver's airbag
module connector

Dummy resistor
(MB991865)
resistance (3Ω)

Resistor harness
(MB991866)

C-204 Clock spring
connector (harness side)

YES

YES (No.61 output)

YES (No.62 output)

SRS AIRBAGS – TROUBLESHOOTING

52B-23

From previous page

Replace the SRS-ECU

Check connectors: C-125, C-204

Confirm the fault symptoms

Check the harness between the
clock spring and the SRS-ECU,
and repair

Replace the
SRS-ECU

(Checking the circuit between the SRS-ECU
and the clock spring)
Measure at SRS-ECU connector C-125
• Detach the SRS-ECU connector C-125
• Detach the clock spring connector C-204
• Ignition switch ON
• Measure at harness side of C-125 SRS-ECU

connector

• Voltage between 11, 12 and body earth

Caution
Do not insert the probe directly into the
terminal from the front side of the
connector, as this may cause a reduction
in contact pressure.

OK: 0V

connector

• Connectivity between 11, 12 and body earth

Caution
Do not insert the probe directly into the
terminal from the front side of the
connector, as this may cause a reduction
in contact pressure.

OK: No connectivity

C-125 connector

YES (No.61 output)

YES (No.62 output)

Repair

harness

• Insert the probe of the resistor harness (MB991866)

• Connect the (–) terminal of the battery.
• After erasing the diagnosis code memory, reconfirm the

diagnosis code.

Is Code No.61 or No.62 output?

SRS AIRBAGS – TROUBLESHOOTING

52B-24

(Type 2)

Replace the clock spring

Replace the
SRS-ECU

Replace the driver’s airbag
module (squib)

Replace the SRS-ECU

Check connectors: C-125, C-203

Confirm the fault symptoms

Check the harness between the
clock spring and the SRS-ECU,
and repair.

Check the clock spring (see p.52B-33)

(Checking the circuit between the SRS-ECU
and the clock spring)
Measure at SRS-ECU connector C-125
• Detach the SRS-ECU connector C-125
• Detach the clock spring connector C-203
• Ignition switch ON
• Voltage between 11, 12 and body earth

Caution
Do not insert the probe directly into the
terminal from the front side of the
connector, as this may cause a reduction
in contact pressure.

OK: 0V

(Checking the circuit between the SRS-ECU
and the clock spring)
Measure at SRS-ECU connector C-125
• Detach the SRS-ECU connector C-125
• Detach the clock spring connector C-203
• Measure at the harness side
• Connectivity between 11, 12 and body earth

Caution
Do not insert the probe directly into the
terminal from the front side of the
connector, as this may cause a reduction
in contact pressure.

OK: No connectivity

Dummy resistor
(MB991865)
resistance (3Ω)

Resistor harness
(MB991866)

C-204 Clock spring
connector (harness side)

C-125 connector

Repair

YES (No.61 output)

YES (No.62 output)

Y1736AU

Y1737AU

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