(G551) ’95-’96 Models.
(G401,G402,G551) ’93-94 Models or
Brake Switch Test
1. If one of the brake lights does not go on, check that
brake light bulb in the taillight or the high mount light
2. If none of the brake lights 90 on, check the No. 45
(20 A) fuse in the under-hood fuse/relay box.
3. If the fuse and bubs are OK, disconnect the 4-P con-
nector from the brake switch.
4-P CONNECTOR
BRAKE
SWITCH
BRAKE
PEDAL
4. Check for continuity between the B and C terminals.
There should be continuity with the brake pedal
pushed.
If there is no continuity, replace the switch or ad-
just pedal height (see section 19).
If there is continuity, but the brake lights do not
go on, inspect for:
Poor ground (G401,G501) ’91-’92 Models or
An open in the WHT/GRN or GRN/WHT wire.
Faulty brake light failure sensors (see page
23-153).
High Mount Brake Light Test
1. Open the trunk lid and engine compartment lid.
2. Disconnect the 2-P connector from the trunk wire
harness.
TRUNK WIRE HARNESS
SIDE WIRE
HARNESS
View from terminal side
View from
terminal
side
3. Connect a voltmeter positive lead to the GRN/WHT
terminal and the negative lead to the BLK terminal
of the side wire harness side of the connector.
Push the brake pedal, and check for voltage between
the GRN/WHT and the BLK terminals. There should
be battery voltage.
If there is no voltage, check for:
— Blown No. 45 (20 A) fuse in the under-hood
fuse/relay box.
— An open in the GRN/WHT or BLK wire.
— Faulty brake switch.
If there is battery voltage, go to step 4.
4. Connect battery power to the GRN/WHT terminal
and ground to the BLK terminal of the trunk wire
harness side of the connector.
Check that all the LEDs of the high mount brake light
go on.
If the high mount brake light does not go on,
check for an open in the wires in the trunk lid.
If the wires in the trunk lid are OK, replace the
high mount brake light.
If some of the LEDs do not go on, replace the high
mount brake light assembly.
GRN/WHT BLK BLK GRN/WHT
(G401,G402,G551) ’93-94 Models or
Brake Switch Test
1. If one of the brake lights does not go on, check that
brake light bulb in the taillight or the high mount light
2. If none of the brake lights 90 on, check the No. 45
(20 A) fuse in the under-hood fuse/relay box.
3. If the fuse and bubs are OK, disconnect the 4-P con-
nector from the brake switch.
4-P CONNECTOR
BRAKE
SWITCH
BRAKE
PEDAL
4. Check for continuity between the B and C terminals.
There should be continuity with the brake pedal
pushed.
If there is no continuity, replace the switch or ad-
just pedal height (see section 19).
If there is continuity, but the brake lights do not
go on, inspect for:
Poor ground (G401,G501) ’91-’92 Models or
An open in the WHT/GRN or GRN/WHT wire.
Faulty brake light failure sensors (see page
23-153).
High Mount Brake Light Test
1. Open the trunk lid and engine compartment lid.
2. Disconnect the 2-P connector from the trunk wire
harness.
TRUNK WIRE HARNESS
SIDE WIRE
HARNESS
View from terminal side
View from
terminal
side
3. Connect a voltmeter positive lead to the GRN/WHT
terminal and the negative lead to the BLK terminal
of the side wire harness side of the connector.
Push the brake pedal, and check for voltage between
the GRN/WHT and the BLK terminals. There should
be battery voltage.
If there is no voltage, check for:
— Blown No. 45 (20 A) fuse in the under-hood
fuse/relay box.
— An open in the GRN/WHT or BLK wire.
— Faulty brake switch.
If there is battery voltage, go to step 4.
4. Connect battery power to the GRN/WHT terminal
and ground to the BLK terminal of the trunk wire
harness side of the connector.
Check that all the LEDs of the high mount brake light
go on.
If the high mount brake light does not go on,
check for an open in the wires in the trunk lid.
If the wires in the trunk lid are OK, replace the
high mount brake light.
If some of the LEDs do not go on, replace the high
mount brake light assembly.
GRN/WHT BLK BLK GRN/WHT