ACURA NSX 1991 Service Repair Manual

Five-step Troubleshooting

1. Verify The Complaint

Turn on all the components in the problem circuit to

verify the customer complaint. Note the symp-

toms. Do not begin disassembly or testing until you

have narrowed down the problem area.

2. Analyze The Schematic

Look up the schematic for the problem circuit.

Determine how the circuit is supposed to work by

tracing the current paths from the power feed

through the circuit components to ground. If

several circuits fail at the same time, the fuse or

ground is a likely cause.

Based on the symptoms and your understanding of

the circuit operation, identify one or more possible

causes of the problem.

3. Isolate The Problem By Testing The Circuit

Make circuit tests to check the diagnosis you made

in step 2. Keep in mind that a logical, simple pro-

cedure is the key to efficient troubleshooting. Test

for the most likely cause of failure first. Try to make

tests at points that are easily accessible.
4. Fix The Problem

Once the specific problem is identified, make the

repair. Be sure to use proper tools and safe

procedures.

5. Make Sure The Circuit Works

Turn on all components in the repaired circuit in all

modes to make sure you've fixed the entire pro-

blem. If the problem was a blown fuse, be sure to

test all of the circuits on that fuse. Make sure no

new problems turn up and the original problem

does not recur.ProCarManuals.com

Relay and Control Unit Locations

Front Compartment

HORN RELAY

A/C COMPRESSOR CLUTCH

RELAY

RADIATOR FAN

LOW RELAY

RADIATOR FAN

HIGH RELAY

CONDENSER FAN RELAY

UNDER-HOOD RELAY BOX A
LEFT HEADLIGHT RETRACTOR

CUT RELAY
WINDSHIELD WIPER

LOW RELAY

WINDSHIELD WIPER

INTERMITTENT RELAY

POWER AMPLIFIER

RELAY
ABS

REAR FAIL-SAFE RELAY

ABS FRONT

FAIL-SAFE RELAY

HEADLIGHT RELAY
RIGHT HEADLIGHT RETRACTOR RELAY

Wire colors: BLU/GRN,

BRN/WHT, BLU/RED,

GRN/YEL, and BLK

LEFT HEADLIGHT RETRACTOR RELAY

Wire colors: BLU/BLK,

WHT/BLK, GRN/RED,

BLU,
and BLK
RIGHT HEADLIGHT RETRACTOR

CUT RELAY

BLOWER RELAY

BLOWER HIGH RELAY

WINDSHIELD WIPER

HIGH RELAY

WINDSHIELD

WASHER RELAY

UNDER-HOOD

RELAY BOX B

DIMMER RELAY

POWER WINDOW

RELAY

TAILLIGHT RELAY

ABS MOTOR RELAY

UNDER-HOOD FUSE/RELAY BOXProCarManuals.com

Relay and Control Unit Locations

Dashboard

TURN SIGNAL/HAZARD

RELAY
CLIMATE CONTROL UNIT

UNDER-DASH FUSE BOX
FOOT WELL LIGHT

DASHBOARD

LOWER COVER

INTEGRATED

CONTROL UNIT
SRS UNITProCarManuals.com

Dashboard, Door and Floor

DRIVER'S DOOR PANEL

ABS CONTROL UNIT

DAYTIME RUNNING

LIGHTS CONTROL

UNIT (Canada)

POWER WINDOW

CONTROL UNIT

STARTER CUT RELAY

Wire colors: BLK/WHT,

BLK/WHT, BLK/GRN,

and BLK/BLU

SECURITY CONTROL UNIT

CIGARETTE LIGHTER

RELAY

Wire colors: YEL/RED,

BLU/GRN, BRN/YEL, and BLK
FOOT WELL BASS SPEAKER
EPS CONTROL UNIT

(Behind foot well

bass speaker)

RIGHT FRONT FLOOR

PANEL

SRS UNIT
POWER DOOR LOCK

CONTROL UNITProCarManuals.com

Relay and Control Unit Locations

Rear Bulkhead

PGM-FI MAIN RELAY
THROTTLE VALVE CONTROL

MOTOR RELAY

Wire colors: BLK,

YEL/BLK, GRN/RED,

and WHT/BLU
TCS CONTROL UNIT
TRANSMISSION CONTROL

MODULE (TCM) (A/T)

PULSE UNIT (M/T)

DASH LIGHTS

BRIGHTNESS

CONTROL UNIT
FAN CONTROL

UNIT

ECMProCarManuals.com

RETRACTABLE HEADLIGH TCONTROL UNI TINTERLOC K CONTRO LUNIT (A/T )
FUEL PUM P RELA YWire colors : YEL , RED ,BLK/YEL , an d BLK/RE D
ProCarManuals.com

Relay and Control Unit Locations

Engine Compartment

REAR WINDOW DEFOGGER

RELAY
ENGINE COMPARTMENT

FAN RELAY (A/T)

Wire colors: YEL/BLK,

BLU/RED, WHT/GRN,

and WHT/BLU

SPARK PLUG VOLTAGE

DETECTION MODULE
ENGINE COMPARTMENT

FUSE/RELAY BOX

IGNITION CONTROL

MODULE (ICM)ProCarManuals.com

Battery
Componen t Locatio n Inde x
BATTER YType: 80D26 L (A/T )
70D23 L (M/T )
CHEC K INDICATO R
HEAT SHIEL D
Replacemen t
1. Remov e th e spar e tir e an d th e spar e tir e holder .
2. Disconnec t bot h th e negativ e cabl e an d positiv e cabl e fro m th e battery .
3. Remov e th e batter y holder , the n tak e ou t th e battery .
SPARE TIR E
SPARE TIRE HOLDER
BATTERY HOLDER
ProCarManuals.com

Battery

Test

• Battery fluid (electrolyte) contains sulfuric acid. It may cause severe burns if it gets on your skin or in your eyes.

Wear protective clothing and a face shield.

— If electrolyte gets on your skin or clothes, rinse it off with water immediately.

— If electrolyte gets in your eyes, flush it out by splashing water in your eyes for at least 15 minutes; call a physician

immediately.

• A battery gives off hydrogen gas. If ignited, the hydrogen will explode and could crack the battery case and splatter

acid on you. Keep sparks, flames, and cigarettes away from the battery.

• Overcharging will raise the temperature of the electrolyte. This may force electrolyte to spray out of the battery vents.

Follow the charger manufacturer's instructions and charge the battery at a proper rate.

Use either a JCI or Bear ARBST tester, and follow the manufacturer's procedures. If you don't have one of these com-

puterized testers, follow this conventional test procedure:

To get accurate results, the temperature of the electrolyte must be between 70°F (21 °C) and 100°F (38°C).

Check For Damage

If the case is cracked or the posts are loose,

replace the battery.

Check Indicator EYE Color

If the indicator shows low electrolyte, add

distilled water if possible.

EYE Indicates OK
EYE Indicates LOW

CHARGE

Test Load Capacity (#1)

Apply 300 amp load for 15 seconds to remove

surface charge.

Allow 15 seconds recovery period.

Apply test load (see Test Load Chart).

Record voltage at the end of 15 seconds.

Stays above 9.6 volts;

battery is OK.
Drops below 9.6 volts.ProCarManuals.com

Charge on High Setting (40 amps)

Charge until EYE shows charge is OK; plus an

additional 30 minutes to assure full charge.

NOTE: If the battery charge is very low, it may

be necessary to bypass the charger's polarity

protection circuitry.

If the EYE does not show charge is OK within

three hours, the battery is no-good; replace it.

Write down how long the battery was charged.

Test Load Capacity (#2)

Apply 300 amp load for 15 seconds to remove surface charge.

Allow 15 seconds recovery period.

Apply test load (see Test Load Chart).

Record voltage at the end of 15 seconds.

Stays above 9.6 volts; battery is OK.

Drops below 9.6 volts; battery is no-good.

80D26L-MF

BATTERY CODEProCarManuals.com