1991 ACURA NSX Service Repair Manual

Troubleshooting

NOTE:

The numbers in the table show the troubleshooting sequence.

Before troubleshooting.

Check the No. 5 (10 A) fuse in the under-dash fuse box, and the No. 29 (50 A) and No. 45 (20 A) fuses in the

under-hood fuse/relay box.

Check that the horns sound.

Check that the tachometer works properly.ProCarManuals.com

Cruise Control
Contro
l
Unit Input Test


CAUTION:
AH SRS wiring harnesses are covered with yellow
outer Insulation.
Before disconnecting any part of the SRS wire
harness, install the short connectors (see page

24-10).
Replace the entire affected SRS harness assembly if

it has an open circuit or damaged wiring.

Remove the glove box, then disconnect the 14-P con-

nector from the control unit and make the following

tests.

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.
SRS
MAIN

HARNESS
CRUISE CONTROL

UNIT

View from

wire side

WHT

GRY

BLK

GRN/WHTLT GRN/RED
LT GRN/BLX

GRN
BRN

BLU/BLK
BLU

YEL
YEL/RED

LT GRN
BLU/ORNProCarManuals.com

ProCarManuals.com

Cruise Control
Main Switch Removal
CAUTION: All SRS wiring harnesses are covered with yellow

outer insulation.

Before disconnecting any part of the SRS wire
harness, install the short connectors (see page

24-10).
Replace the entire affected SRS harness assembly if

it 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
3. Remove the steering column lower cover and upper
cover.
UPPER COVER

LOWER COVER

4. Disconnect the 16-P connector and the 10-P
connector.

10-P

CONNECTOR
16-P CONNECTOR
CAUTION: Be careful not to damage the SRS wire
harness.ProCarManuals.com

5. Remove the four screws and remove the combina-

tion light switch (main switch).

COMBINATION LIGHT SWITCH
10-P CONNECTOR

16-P CONNECTOR
Main Switch Test
1. Remove the dashboard lower panel and knee bolster pad.
2. If necessary, remove the knee bolster.
3. Disconnect the 16-P connector and check for con- tinuity between the terminals in each switch posi-
tion according to the table.

CRUISE

MAIN

SWITCH

16-P CONNECTOR

View from terminal sideProCarManuals.com

5. Remove the four screws and remove the combina-

tion light switch (main switch).

COMBINATION LIGHT SWITCH

10-P CONNECTOR

16-P CONNECTOR
Main Switch Test

1. Remove the dashboard lower panel and knee

bolster pad.

2. If necessary, remove the knee bolster.

3. Disconnect the 16-P connector and check for con-

tinuity between the terminals in each switch posi-

tion according to the table.

CRUISE

MAIN

SWITCH

16-P CONNECTOR

View from terminal sideProCarManuals.com

Cruise Control

A/T Gear Position Switch Test
1. Remove the front console, then disconnect the 12-P connector from the A/T gear position switch.
2. Check for continuity between the terminals in each
switch position according to the table.

Move the lever back and forth at each position without touching the push button and check for
continuity within the range of free play of the
shift lever.

If
there
is no
continuity
within
the
range
of
free

play, adjust the position of the A/T gear position
switch (see page 23-160).

A/T GEAR POSITION SWITCH
12-P CONNECTOR
View from wire side.

A/T Gear Position Switch (For cruise control)
Actuator Assembly Test

1. Disconnect the 4-P connector from the actuator assembly.
2. Check that the output linkage moves smoothly.
3. Connect battery power to the D terminal and ground to the A terminal.

MOTOR

ACTUATOR

ASSEMBLY

OUTPUT
LINKAGE

4. Check for a clicking sound from the magnetic clutch and that the output linkage is locked.
You should be able to hear the motor.
5. If the output linkage is not locked, replace the ac- tuator assembly.
6. Check the operation of the actuator motor in each
output linkage position according to the table.

You should be able to hear the motor.

FULLY

OPEN
OUTPUT

LINKAGE

MIDDLE

POSITION
FULLY CLOSEDProCarManuals.com

Actuator Cable Adjustment
1. Check that the actuator cable moves smoothly
with no binding or sticking.

2. Start the engine and warm it up to normal operating temperature (radiator fan comes on).
3. Measure how far the output linkage moves before the engine speed starts to increase.
Make sure you begin with the linkage at the fully
closed position. Free play should be 11 ± 1.5 mm (0.43
±
0.06 in).

OUTPUT
LINKAGE
ADJUSTING NUT

ACTUATOR

CABLE

LOCKNUT
FREE PLAY:

11 ± 1.5 mm
(0.43
±
0.06
in)

FULLY CLOSED POSITION
4. If the free play is not within specs, loosen the lock- nut and turn the adjusting nut as required.
NOTE: If necessary, check the throttle control
system (see section 11), then recheck the output
linkage free play.
5. Retighten the locknut and recheck the free play.ProCarManuals.com