1991 ACURA NSX service

If the inspection for a particular DTC requires the use of Test Harness (07LAJ—PT3010A):
Connect the wire harness to the Test Harness, and/or connect the Test Harness to the TCM according to the

troubleshooting flowchart.

TCM

TEST HARNESS

Terminal Locations

TCM Reset Procedure

Turn the ignition switch off. -

, Remove the CLOCK fuse (7.5 A) from the main relay box for 10 seconds to reset the TCM.

1

2

NOTE: Disconnecting the CLOCK fuse also cancels the radio preset stations and the clock setting. Make note of the
radio presets before removing the fuse so you can reset them.
Final Procedure NOTE: This procedure must be done after any troubleshooting.
1. Remove the jumper wire from the Service Check Connector.
2. Reset the TCM. 3. Set the radio preset stations and clock setting.
Only the A and D terminals of the Test Harness are used for A/T troubleshooting.

Unless otherwise noted, use only the Digital Multimeter, KS—AHM —32—003, for testing.

07LAJ-PT3010A

NOTE:ProCarManuals.com

Symptom-to-Component Chart
Electrical System
Number of indicator light

blinks while Service Check
Connector is jumped.
When the ignition

switch is turned on,
indicator light
1

Blinks

Possible Cause


Symptom

Lock-up clutch does not

engage.
Lock-up clutch does not

disengage.
Unstable idle speed.
Refer to

page

14-54

14-55

14-56

14-57

14-58

14-60
14-62
14-63
14-64
14-66

Lock-up clutch does not

engage.
Lock-up clutch does not

engage.
Fails to shift (stuck in 1 st or 4th

gears).
Fails to shift other than 2nd

4th gears.
Lock-up clutch does not

engage.
Lock-up clutch engages and
disengages alternately. Fails to shift other than 2nd

4th gears.
Lock-up clutch does not

engage.
Lock-up clutch does not

engage.
Lock-up clutch does not

engage.
Lock-up clutch does not

engage.

Disconnected lock-up control
solenoid valve A connector Short or open in lock-up control
solenoid valve A wire
Faulty lock-up control solenoid
valve A
Disconnected lock-up control
solenoid valve B connector Short or open in lock-up control
solenoid valve B wire

Faulty lock-up control solenoid

valve B
Disconnected throttle position(TP) sensor connector
Short or open in TP sensor wire
Faulty TP sensor
Disconnected vehicle speed
sensor (VSS) connector
Short or open in VSS wire
Faulty VSS
Short in A/T gear position
switch wire
Faulty A/T gear position switch
Disconnected A/T gear position
switch connector
Open in A/T gear position
switch wire Faulty A/T gear position switch
Disconnected shift control
solenoid valve A connector Short or open in shift control
solenoid valve A wire
Faulty shift control solenoid
valve A
Disconnected shift control
solenoid valve B connector
Short or open in shift control
solenoid valve B wire
Faulty shift control solenoid
valve B
Disconnected countershaft
speed sensor connector
Short or open in countershaft
speed sensor wire Faulty countershaft speed sen-

sor

Disconnected engine coolant
temperature (ECT) sensor
connectorShort or open in ECT sensor
wire Faulty ECT sensor
Blinks

10

9


Blinks
Blinks

8
7
Blinks

6

OFF

Blinks

5

4


Blinks

3


Blinks or OFF Blinks

2

Fails to shift (between 1 st
4th,
2nd
4th or 2nd

3rd

gears only).
Fails to shift (stuck in 4th gear)ProCarManuals.com

If a customer describes the symptoms for codes 3, 6, 11, 14 or 1 5 yet the indicator light is not blinking, it will
be necessary to recreate the symptom by test driving, and then checking the indicator light with the ignition

still
ON.
If the indicator light displays codes 1,2,3,8, 11, or 16, check first the No. 9, 13 and 18 and fuse before elec-
trical troubleshooting.
If any of the fuses have blown, repair them and then recheck. If the indicator light displays codes other than those listed above or stays lit continuously, the TCM is faulty.
Sometimes the indicator light and the Malfunction Indicator Lamp (MID/Check Engine light may come on
simultaneously. If so, check the PGM-FI system according to the number of blinks on the MIL/Check Engine light,
then reset the memory by removing the CLOCK fuse in the main relay box for more than 10 seconds. Drive the vehicle for several minutes at speed over 30 mph (50 km/h), then recheck the MIL/Check Engine light.PGM-FI system

The PGM-FI system on this model is a sequential multiport fuel injectin system.
The indicator light may comes on, indicating a system problem, when, in fact, there is a poor or intermittent
electrical connection. First, check the electrical connections, clean or repair connections if necessary.If the electrical readings are not as specified when using the test harness, check the test harness connections
before proceeding.
Disconnecting the CLOCK fuse also cancels the radio preset stations and the clock setting. Make note of the radio
presets before removing the fuse so you can reset them. If the self-diagnosis indicator light does not blink, perform an inspection according to the table listed below.
Symptom
• Lock-up clutch does not
engage.

• Transmission jerks hard when shifting.
• Transmission jerks hard when
shifting.

• Transmission jerks hard when
shifting

• Lock-up clutch does not

engage.
14-7214-70 14-68
14-67

Refer to

page

Possible Cause
• Disconnected gauge assembly connector
• Short or open in tachometer wire
• Faulty tachometer
• Short or open in FAS (PNK) wire between D16 terminal and

ECM.

• Trouble in ECM
• Disconnected mainshaft speed sensor connector
• Short or open in mainshaft speed sensor wire
• Faulty mainshaft speed sensor
• Disconnected linear solenoid connector
• Short or open in linear solenoid wire
• Faulty linear solenoid
Blinks

OFF

OFF

OFF

When the ignition

switch is turned on,
indicator light
Number of indicator light

blinks while Service CheckConnector is jumped.

11

14

15

16


Ref.page

14-74
14-76
14-77
14-78
NOTE:ProCarManuals.com

2ND GEAR SPACER
COTTER
FEELER GAUGE
2ND GEAR
3RD GEAR COTTER
2ND GEAR SPACER
6. After replacing the cotters, make sure that the

clearance is held within tolerance.

7. Remove the countershaft bearing from the trans-
mission housing. See page 14-144.

8. Assemble the countershaft including bearing and
all parts shown to on page 14-124.

5. If the clearance is out of tolerance, select and install a

new cotters.

COTTER 31.5 mm
Countershaft

Inspection/Installation (cont'd)

3. If the clearance is out of tolerance; -1. Select and install a new 3rd gear collar andrecheck the clearance.
-2. If the clearance is still out of tolerance, replace the two thrust needle bearings and recheck the
clearance.

If the clearance still exceeds the service limit even

with new thrust needle bearings, check the 3rd

gear, 2nd gear and 3rd gear collar for wear, and

replace any worn parts.
After replacing parts, make sure that the clearance

is within tolerance.

NOTE:

4. Hold the 2nd gear against the 3rd gear. Measure the clearance between the 2nd gear spacer and cotters

with a feeler gauge.

NOTE: Take measurements in at least three places,
and take the average as the actual clearance.ProCarManuals.com

Clutch

Reassembly (cont'd)

14. Measure the clearance between the clutch end plate

and top disc with a dial indicator. Zero the dial indicator

with the clutch end plate lowered and lift it up to the

snap ring. The distance that the clutch end plate

moves is the clearance between the clutch end plate

and top disc.

NOTE: Measure at three locations.

End Plate-to-Top Disc Clearance:
15. If the clearance is not within the service limits, select a

new clutch end plate from the following table.

NOTE: If the thickest clutch end plate is installed but

the clearance is still over the standard, replace the

clutch discs and clutch plates.

2ND, 3RD, 4TH and 1ST HOLD CLUTCH

END PLATE
TOP DISC

1ST CLUTCH

PLATE NUMBER

Thickness

END PLATEProCarManuals.com

Inspection

Steering Wheel Rotational Play
1. Place the front wheels in a straight ahead position and measure the distance the steering wheel can be
turned without moving the front wheels.

2. If the
play
exceeds
the
service
limit,
check
all
steer- ing components.
Service Limit: 5 mm (0.2 in) maximum
Steering Effort Check (Manual Steering Only)
Operation Standard

Turn the steering wheel with a spring scale. Read the
measurement when the front wheels or steering wheel
start to move.Power Assist Check With Car
Parked (Electrical Power Steering

Only)

1. Raise the front wheels off the ground (see sec-
tion 1).

2. Turn the steering wheel with a spring scale and check its reading.
3. If the reading exceeds the service limit, adjust the steering gearbox as shown on the next page.
Service Limit: 20 N (2 kg, 4 Ibs) maximum Condition
Without power assist (engine off)
With power assist (engine running) Stationary Swing
operation load

120 N (12 kg, 26
Ibs)
maximum

42 N
(4.2
kg, 9.3
Ibs) maximumProCarManuals.com

Removal (cont'd)

7. Disconnect the connectors from the horn and cruise control set/resume switches remove the airbag con-nector from its dips.

CRUISE CONTROL

SET/RESUME SWITCHES

4-P CONNECTOR
HORN
CONNECTOR

Disassembly/Reassembly
Store a removed airbag assembly with the
pad surface up. If the airbag is improperly stored face
down, accidental deployment could propel the unit with
enough force to cause serious injury.
NOTE: If an intact airbag assembly has been removed
from a scrapped car or has been found defective or

damaged during transit, storage or service, it should be
deployed (see section 23).

STEERING WHEELLOWER COVER STEERING WHEEL
ACCESS PANEL CRUISE CONTROL SET/RESUME SWITCH STEERING
WHEEL NUT
Replace. TORX
®
BOLT

10 N ·
m

(1.0 kg-m, 7 lb-ft)

Replace. AIRBAG ASSEMBLY

CAUTION:
Carefully inspect the airbag assembly before install-
ing. Do not install an airbag assembly that shows signs
of being dropped or improperly handled, such as dents,
cracks or deformation.
Always keep the short connector on the airbag con- nector when the harness is disconnected.
Do not disassemble or tamper with the airbag as-

sembly.
STEERING WHEEL

NUT
Replace.

8. Remove the steering wheel nut.
9. Remove the steering wheel by rocking it slightly from

side-to-side as you pull steadily with both hands.ProCarManuals.com

Removal (cont'd)

7. Disconnect the connectors from the horn and cruise control set/resume switches remove the airbag con-nector from its dips.

CRUISE CONTROL

SET/RESUME SWITCHES

4-P CONNECTOR
HORN
CONNECTOR

Disassembly/Reassembly
Store a removed airbag assembly with the
pad surface up. If the airbag is improperly stored face
down, accidental deployment could propel the unit with
enough force to cause serious injury.
NOTE: If an intact airbag assembly has been removed
from a scrapped car or has been found defective or

damaged during transit, storage or service, it should be
deployed (see section 23).

STEERING WHEELLOWER COVER STEERING WHEEL
ACCESS PANEL CRUISE CONTROL SET/RESUME SWITCH STEERING
WHEEL NUT
Replace. TORX® BOLT

10 N .
m

(1.0 kg-m, 7 lb-ft)

Replace. AIRBAG ASSEMBLY

CAUTION:
Carefully inspect the airbag assembly before install-
ing. Do not install an airbag assembly that shows signs
of being dropped or improperly handled, such as dents,
cracks or deformation.
Always keep the short connector on the airbag con- nector when the harness is disconnected.
Do not disassemble or tamper with the airbag as-

sembly.
STEERING WHEEL

NUT
Replace.

8. Remove the steering wheel nut.
9. Remove the steering wheel by rocking it slightly from

side-to-side as you pull steadily with both hands.ProCarManuals.com