Honda Civic. Manual — part 937

MICU INPUT TEST (CONNECTORS DISCONNECTED)

Cavity Wire

Test

condition

Test: Desired result

Possible cause if

result is not

obtained

G16

WHT

Under all

conditions

Check for voltage to
ground: There should be
battery voltage.

Blown No. 12
(15 A) fuse in
the under-hood
fuse/relay box

An open in the
wire

G18

WHT

Under all

conditions

Check for voltage to
ground: There should be
battery voltage.

Blown No. 4
(50 A) fuse in
the under-hood
fuse/relay box

An open in the
wire

G7

LTGRN

Under all

conditions

Connect G16 and G7
terminals with a jumper
wire momentarily: The
horn should sound.

Poor ground
(body ground)

Blown No. 12
(15 A) fuse in
the under-hood
fuse/relay box

Faulty horn

An open in the
wire

E20

GRN

Under all

conditions

Connect G2 and E20
terminals with a jumper
wire: The trunk release
actuator should work
(Trunk lid should open).

Poor ground
(G701)

Faulty trunk
release actuator

An open in the
wire

Connect battery power

Faulty driver's

2008 Honda Civic LX

2006-08 ACCESSORIES & EQUIPMENT Keyless/Power Door Locks/Security System - Civic (All Except Hybrid)

6. Reconnect the connectors to the under-dash fuse/relay box, and make these

input tests at the connectors.

If any test indicates a problem, find and correct the cause, then recheck the
system.

If all the input tests prove OK, the MICU must be faulty; replace the
under-dash fuse/relay box.

MICU INPUT TEST (CONNECTORS RECONNECTED)

N7

BLU

Under all

conditions

to the N13 terminal and
ground the N7 terminal
momentarily: The
driver's door lock
actuator should lock.

door lock
actuator

An open in the
wire

N13

YEL

M8

YEL

Under all

conditions

Connect battery power
to the M8 terminal and
ground the M10 terminal
momentarily: The front
passenger's door lock
actuator should unlock.

Faulty front
passenger's
door lock
actuator

An open in the
wire

M10

BLU

E1 (4-

door)

YEL

Under all

conditions

Connect battery power
to the E1 terminal and
ground the E21 terminal
momentarily: The right
rear door lock actuator
should unlock.

Faulty right
rear door lock
actuator

An open in the
wire

E21 (4-

door)

BLU

E14 (4-

door)

YEL

Under all

conditions

Connect battery power
to the E14 terminal and
ground the E31 terminal
momentarily: The left
rear door lock actuator
should unlock.

Faulty left rear
door lock
actuator

An open in the
wire

E31 (4-

door)

BLU

Cavity

Wire

Test condition

Test:

Desired

Possible cause if

result is not obtained

2008 Honda Civic LX

2006-08 ACCESSORIES & EQUIPMENT Keyless/Power Door Locks/Security System - Civic (All Except Hybrid)

result

E6

BLK

Under all conditions

Check for
voltage to
ground:
There
should be
less than
0.5 V.

Poor ground
(G602)

An open in the
wire

E33

BLK

Under all conditions

Check for
voltage to
ground:
There
should be
less than
0.5 V.

Poor ground
(G601)

An open in the
wire

F20

BLK

Under all conditions

Check for
voltage to
ground:
There
should be
less than
0.5 V.

Poor ground
(G401)

An open in the
wire

T34

BLK

Under all conditions

Check for
voltage to
ground:
There
should be
less than
0.5 V.

Poor ground
(G501)

An open in the
wire

Right rear door open

Check for
voltage to
ground:
There
should be
less than 1

Faulty right rear
door switch

An open in the
wire

2008 Honda Civic LX

2006-08 ACCESSORIES & EQUIPMENT Keyless/Power Door Locks/Security System - Civic (All Except Hybrid)

E2 (4-

door)

GRY

V.

Right rear door

closed

Check for
voltage to

ground:

There

should be 5

V or more.

Faulty right rear
door switch

Short to ground
in the wire

E3

LTGRN

Front passenger's

door open

Check for
voltage to
ground:
There
should be
less than 1
V.

Faulty front
passenger's door
switch

An open in the
wire

Front passenger's

door closed

Check for
voltage to

ground:

There

should be 5

V or more.

Faulty front
passenger's door
switch

Short to ground
in the wire

E17 (4-

door)

BRN

Left rear door open

Check for
voltage to
ground:
There
should be
less than 1
V.

Faulty left rear
door switch

An open in the
wire

Left rear door closed

Check for
voltage to

ground:

There

should be 5

V or more.

Faulty left rear
door switch

Short to ground
in the wire

Check for
voltage to

Poor ground

2008 Honda Civic LX

2006-08 ACCESSORIES & EQUIPMENT Keyless/Power Door Locks/Security System - Civic (All Except Hybrid)