ACURA NSX 1991 Service Repair Manual

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

Lock-up Control Solenoid Valve A/B

Test

NOTE: Lock-up control solenoid valves A and B must be
removed/replaced as an assembly.
1. Disconnect the connector from the lock-up control solenoid valve A/B.
2. Measure the resistance between the No. 1 terminal
(solenoid valve A) of the lock-up control solenoid

valve connector and body ground and between the No. 2 terminal (solenoid valve B) and body ground.

View from

terminal side.

3. Replace the lock-up control solenoid valve assembly if the resistance is out of specification.
4. If the resistance is within the standard, connect the
No. 1 terminal of the lock-up control solenoid valve

connector to the battery positive terminal. A click-
ing sound should be heard. Connect the No. 2 ter-
minal to the battery positive terminal. A clicking
sound should be heard. Replace the lock-up controlsolenoid valve assembly if no clicking sound is

heard.
3. Clean the mounting surface and oil passages of the

lock-up control solenoid valve assembly and install
a new filter/gasket.
4. Check the connector for rust, dirt or oil and reconnect it securely.
6 x 1.0 mm

12 N.m (1.2 k-gm, 9 Ib-ft)

FILTER/GASKET
Replace.

LOCK-UP CONTROL

SOLENOID VALVE

ASSEMBLYClean mounting surface
and oil passages.
1. Remove the mounting bolts and lock-up control sole-
noid valve assembly.
2. Check the lock-up control solenoid valve oil passages for dust or dirt and replace as an assembly, if
necessary.

Replacement

STANDARD: 12
LOCK-UP CONTROL

SOLENOID VALVE

ASSEMBLYProCarManuals.com

Shift Control Solenoid Valve A/B

Test

NOTE: Shift control solenoid valves A and B must be re-

moved/replaced as an assembly.

1. Disconnect the connector from the shift control sole-
noid valve A/B.

2. Measure the resistance between the No. 1 terminal (solenoid valve A) of the shift control solenoid
valve connector and body ground and between the No. 2 terminal (solenoid valve B) and body ground.

SHIFT CONTROL

SOLENOID VALVE

ASSEMBLY
View from

terminal side.

3. Replace the shift control solenoid valve assembly if the resistance is out of specification.
4. If the resistance is within standard, connect the No. 1 terminal of the shift control solenoid valve
connector to the battery positive term inal. A click-
ing sound should be heard. Connect the No. 2 ter-
minal to the battery positive terminal. A clicking
sound should be hear. Replace the shift control
solenoid valve assembly if no clicking sound is heard.
3. Clean the mounting surface and oil passages of the

shift control solenoid valve assembly and install a
new filter/gasket.
4. Check the connector for rust, dirt or oil and reconnect
it securely.

6 X 1.0 mm

12N .
m

(1.2kg-m, 9 Ib-ft)
FILTER/GASKET

Replace.
Clean mounting
surface and oil
passages.

SHIFT CONTROL

SOLENOID VALVE

ASSEMBLY
1. Remove the mounting bolts and shift control solenoid

valve assembly.

2. Check the shift contol solenoid valve oil passages for dust or dirt and replace as an assembly, if necessary.

ReplacementProCarManuals.com

Linear Solenoid

Test

1. Remove the linear solenoid connector.
2. Measure the resistance between the A and B terminal.

LINEAR
SOLENOID
View from terminal side
3. Replace the linear solenoid if resistance is out of specification.
4. Connect the B terminal of the linear solenoid con- nector to the battery positive terminal and the A
terminal to the battery negative terminal. A clicking sound should be heard.
5. If not, replace the linear solenoid.

LINEAR SOLENOID INSTALLATION DISTANCE:
Measurement of distance

THROTTLE

VALVE BODY

LINEAR SOLENOID

SHIM
LINEAR SOLENOID

LINEAR SOLENOID

INSTALLATION
DISTANCE

Measurement of
distance.
Clean the mounting

surface.

NOTE: Select the appropriate shim when the linear sole-
noid is replaced.
1. Remove the linear solenoid and shim from the trans- mission housing.
2. Clean the mounting surface.
3. Measure the distance between the mounting surface of the linear solenoid and the throttle valve body.

Replacement

23.5 – 23.7 mm (0.925 – 0.933 in)
NOTE: If the measurement of distance is 21.6 mm (0.850 in), select the shim of 2.0 mm (0.079 in) to ob-
tain the installation distance of 23.6 mm (0.929 in).
(cont'd)

STANDARD: 5.0


5.5

(at 70°F, 20°C)ProCarManuals.com

Linear Solenoid

Replacement (cont'd)

4. Select a new shim from the chart below. NOTE: Identification color is painted on the side of

the shim.

LINEAR SOLENOID

SHIM

LINEAR SOLENOID SHIM 5. Apply liquid gasket to both sides of the linear
solenoid shim as shown. Use liquid gasket Part No.

08718–0001.

CAUTION:
Install the linear solenoid within 10 minute of
applying the liquid gasket.
After installation, wipe off any liquid gasket, that squeezed out from around the linear solenoid

shim.

NOTE:
Check that the mounting surfaces are clean and

dry before applying liquid gasket. Degrease if

necessary.

Apply the liquid gasket evenly. Do not install the parts if 10 minutes or more has
passed since you first applied the liquid gasket.If 10 minutes has passed, reapply liquid gasket
after removing the residue.

Wait at least 30 minutes before filling with oil.
Do not apply liquid gasket
here on either side.

Apply liquid gasket
here on both side.

5–10
mm

(
0.197–0.394 in)


6. Install the linear solenoid and shim to the

transmission housing.

6 x 1.0 mm
10N·m

(1.0
kg-m. 7 Ib-ft)
Clean mounting surface.


LINEAR SOLENOID

SHIM

O-RING
Replace.
LINEAR SOLENOIDProCarManuals.com

Mainshaft/Countershaft

Speed Sensors

Replacement

1. Remove the 6 mm bolt from the transmission hous- ing and remove the mainshaft and countershaft
speed sensors.
2. Replace the O-ring with a new one before reassembling the mainshaft and countershaft
speed sensors.
3. Install the washer on the countershaft speed sensor.
NOTE: Do not install the washer on the mainshafl
speed sensor.
4. Install the speed sensor(s) in the transmission
housing.
6 x 1.0 mm
12 N .
m (1.2 kg-m, 9 Ib-ft)
COUNTERSHAFT SPEED
SENSOR WASHER
COUNTERSHAFT SPEED
SENSOR
MAINSHAFT SPEED SENSOR

6 x 1.0 mm
12 N·m (1.2 kg-m, 9 Ib-ft)
ProCarManuals.com

Symptom-to-Component Chart

Hydraulic SystemProCarManuals.com

(cont'd)ProCarManuals.com

Symptom-to-Component Chart

Hydraulic System (cont'd)ProCarManuals.com

ProCarManuals.com