ACURA NSX 1991 Service Repair Manual
Manufacturer: ACURA, Model Year: 1991, Model line: NSX, Model: ACURA NSX 1991Pages: 1640, PDF Size: 60.48 MB
Page 1411 of 1640

Lighting System
Retractable Headlight Control Unit Input Test
Remove the rear bulkhead panels and disconnect the 18-P connector from the control unit.
Inspect the connector terminals to be sure they are all
making good contact.
If the terminals are bent, loose, or corroded, repair
them as necessary, and recheck the system.
If the terminals look OK, make the following input
tests at the connector.
If any test indicates a problem, find and correct
the cause, then recheck the system.
If all the input tests prove OK, the control unit
must be faulty; replace it.
NOTE: Different wires with the same color have
been given a number suffix to distinguish them
(for example, RED/YEL1 and RED/YEL4 are not
the same). REAR BULKHEAD
RETRACTABLE HEADLIGHT
CONTROL UNIT
View fromwire side
RED/GRN2
PNK/BLK
LT GRN/RED
YEL/WHT
YEL
YEL/BLU
YEL/GRN
WHT/YEL
GRN/WHT1
RED/YEL1
18-P CONNECTOR
BLU1
BLU/RED
BLK1
WHT/GRN
BLK2
RED/YEL4ProCarManuals.com
Page 1412 of 1640

ProCarManuals.com
Page 1413 of 1640

Lighting System
Daytime Running Lights Control Unit Input Test (Canada)
Remove the glove box lower panel and glove box.Dis-
connect the 4-P and 8-P connectors from the daytime
running lights control unit.
Inspect the connector terminals to be sure they are all
making good contact.
If the terminals are bent, loose, or corroded, repair
them as necessary, and recheck the system.
If the terminals look OK, make the following input tests
at the connector.
If any test indicates a problem, find and correct the
cause, then recheck the system.
If all the input tests prove OK, the control unit must
be faulty; replace it.
4-P CONNECTOR
DAYTIME RUNNING LIGHTS
CONTROL UNIT (Canada)
8-P CONNECTOR
View from wire side
GRN/YEL
GRN/REDProCarManuals.com
Page 1414 of 1640

Combination Light /Turn Signal Switch Test
16-P CONNECTOR
1. Remove the dashboard lower cover and knee bolster
pad.
2. If necessary, remove the knee bolster.
3. Disconnect the 16-P connector from the floor wire
harness.
4. Check for continuity between the terminals, in each
switch position according to the table.
View from wire side
Turn Signal Switch
Headlight/Dimmer/Passing SwitchProCarManuals.com
Page 1415 of 1640

Lighting System
Headlight/Turn Signal Switch Replacement
CAUTION:
All SRS wiring harnesses are covered with yellow out-
e
r
insulation.
Before disconnecting any part of the SRS wire har-
ness, install the short connectors (page 24-10('93-'96)). Replace the entire affected SRS harness assembly If
ft has an open circuit or damaged wiring.
SRS MAIN
HARNESS
1. Remove the knee bolster pad.
KNEE BOLSTER PAD
2.
Remove
the
tilt
cover.
TILT COVER
16-P CONNECTOR
10-P
CONNECTOR
4. Disconnect the 16-P connector and 10-P connector.
LOWER COVERUPPER COVER
3. Remove the steering column lower cover and upper
cover.ProCarManuals.com
Page 1416 of 1640

5. Remove the four screws from the headlight switch.
HEADLIGHT SWITCH 10-P CONNECTOR
16-P CONNECTOR
6. Disconnect the 10-P connector from the turn signal cancel unit, then remove the headlight switch and
turn signal switch.
7. Separate the headlight switch from the turn signal switch.
8. If necessary, remove the turn signal cancel unit and cancel switch.
TURN SIGNAL CANCEL UNIT TURN SIGNAL
CANCEL SWITCH
HOUSING
BULB (0.91 W)
4. Remove the bulb from the switch by turning it 45°. 3. Slide the headlight switch out of the housing as
shown.
HEADLIGHT SWITCH
1. Remove the headlight switch (see previous page).
2. Remove the two screws. Headlight Switch Light Bulb
ReplacementProCarManuals.com
Page 1417 of 1640

5. Remove the four screws from the headlight switch.
HEADLIGHT SWITCH 10-P CONNECTOR
16-P CONNECTOR
6. Disconnect the 10-P connector from the turn signal cancel unit, then remove the headlight switch and
turn signal switch.
7. Separate the headlight switch from the turn signal switch.
8. If necessary, remove the turn signal cancel unit and cancel switch.
TURN SIGNAL CANCEL UNIT TURN SIGNAL
CANCEL SWITCH
HOUSING
BULB (0.91 W)
4. Remove the bulb from the switch by turning it 45°. 3. Slide the headlight switch out of the housing as
shown.
HEADLIGHT SWITCH
1. Remove the headlight switch (see previous page).
2. Remove the two screws. Headlight Switch Light Bulb
ReplacementProCarManuals.com
Page 1418 of 1640

Side Marker/Turn Signal/Hazard Flash System
Turn Signal/Hazard Relay Input Test
1. Remove the dashboard lower cover. Remove the turn signal/hazard relay from the left kick panel, then dis-
connect the 6-P connector.
2. Inspect the connector terminals to be sure they are all making good contact.
If the terminals are bent, loose or corroded, repair
them as necessary, and recheck the system.
If the terminals look OK, make the following in-
put tests at the connector. If any test indicates a problem, find and cor-
rect the cause, then recheck the system. If all the input tests prove OK, the control unit
must be faulty; replace it.
View from
wire side
TURN/SIGNAL
HAZARD RELAY
1
2
3
4
5
6
B
(RED/WHT)
SR
(BLU/YEL)
SL
(BLU/GRN)
SR
(BLU/YEL)
SL
(BLU/GRN)
LR
(GRN/YEL)
LL
(GRN/BLU)
Test condition
Under all conditions.
Ignition switch ON
and turn signal
switch in right position.
Ignition switch ON
and turn signal switch in left
position.
Connect the B termi-
nal to the LR
terminal.
Connect the B termi-
nal to the LL
terminal.
Test: Desired result
Check for continuity to ground:
There should be continuity.
Check for voltage to ground:
There should be battery voltage.
Check for voltage to ground:
There should be battery voltage.
Check for voltage to ground:
There should be battery voltage.
Right turn signal lights should come
on.
Left turn signal lights should come
on.
Possible cause if result is not obtained
Poor ground (G401, G402).
An open in the wire.
Blown No. 46 (10 A) fuse.
An open in the wire.
Blown No. 5 (10 A) fuse.
Faulty turn signal switch or cancel
unit.
An open in the wire.
Faulty hazard warning switch.
An open in the wire.
Blown bulb.
Faulty side marker flasher circuit.
Poor ground (G301, G401, G402,
G551).
An open in the wire.
Blown bulb.
Faulty side marker flasher circuit.
Poor ground (G301, G401, G402,
G551).
An open in the wire.
E
(BLK)
Terminal
No.
Under all conditions.
Hazard warning
switch ON.ProCarManuals.com
Page 1419 of 1640

Cancel Unit Input Test
1. Remove the steering column covers. Disconnect the 10-P connector from the turn signal cancel unit.
2. Inspect the connector terminals to be sure they are all making good contact.
If the terminals are bent, loose or corroded, repair
them as necessary, and recheck the system.
If the terminals look OK, make the following in-
put tests at the connector. If any test indicates a problem, find and cor-
rect the cause, then recheck the system. If all the input tests prove OK, the control unit
must be faulty; replace it.
C9 (GRN/BLK)
C10
(BLK)
10-P CONNECTOR
TURN SIGNAL
CANCEL UNIT
C7 (BLU/YEL)
C5
(PUR)
C3(ORN)
C1
(YEL)
View
from
wire
side
C2
(BRN)
C4
(WHT)
C6
(GRY)
C8 (BLU/GRN)
Test condition
Under all conditions.
Ignition switch ON.
Headlight switch
Turn signal switch in right position.
Turn signal switch in
left position.
Under all conditions.
Connect the C1
terminal to the C7
terminal, then turn
the ignition switch
ON.
Connect the C1
terminal to the C8
terminal, then turn
the ignition switch
ON.
Test: Desired result
Check for continuity to ground:
There should be continuity.
Check for voltage to ground:
There should be battery voltage.
Check for voltage to ground:
There should be battery voltage.
Check for continuity between the
C2 and C6 terminals:
There should be continuity.
Check for continuity between the
C2 and C9 terminals:
There should be continuity.
Check for continuity between the
C3 and C4 terminals:
There should be continuity.
Right turn signal lights should come
on.
Left turn signal lights should come
on.
Possible cause if result is not obtained
Poor ground (G401, G402).
An open in the wire.
Blown No. 5 (10 A) fuse.
An open in the wire.
Faulty headlight switch or taillight
relay.
An open in the wire.
Faulty turn signal switch.
An open in the wire.
Faulty turn signal switch.
An open in the wire.
Faulty cancel solenoid.
An open in the wire.
Blown bulb.
Faulty turn signal/hazard relay.
Poor ground (G301, G401, G402,
G551).
An open in the wire.
Blown bulb.
Faulty turn signal/hazard relay.
Poor ground (G301, G401, G402,
G551).
An open in the wire.
No.
Terminal
C10
(BLK)
1
2
C1
(YEL)
C5
(PUR)
3
4
C2
(BRN)
C6
(GRY)
5
C2
(BRN)
C9
(GRN/BLK)
6
C3
(ORN)
C4
(WHT)
7
C7
(BLU/YEL)
C8
(BLU/GRN)ProCarManuals.com
Page 1420 of 1640

Side Marker/Turn Signal/Hazard Flasher System
Hazard Warning Switch Removal
CAUTION: All SRS wiring harnesses are covered with yellow out-
er insulation.
Before disconnecting any part of the SRS wire har-
ness, Install the short connectors (see page 24-10) Replace the entire affected SRS harness assembly if
it ha* an open circuit or damaged wiring.
1. Remove the dashboard lower cover and disconnect
the connectors from the floor wire harness.
CONNECTORS
DASHBOARD
LOWER COVER
2. Disconnect the 18-P connector from the floor wire
harness.
HAZARD WARNING
SWITCH
18-P
CONNECTOR
3.
Remove
the
tilt
cover.
TILT COVER
4. Remove the steering column tower cover and upper
cover. Be careful not to damage them.
5. Remove the four screws, then remove the hazard
warning switch and wiper switch.
HAZARD
WARNING
SWITCH
WIPER SWITCHProCarManuals.com