Page 578 of 2395
SEF943Y
SEF572X
b) Connect No. 1 ignition coil and No. 1 spark plug with suitable
high-tension wire as shown, and attach timing light clamp to
this wire.
c) Check ignition timing.
SEF311Q
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment
NBEC0028PREPARATIONNBEC0028S011) Make sure that the following parts are in good order.
IBattery
IIgnition system
IEngine oil and coolant levels
IFuses
IECM harness connector
IVacuum hoses
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BASIC SERVICE PROCEDURE
How to Check Idle Speed and Ignition Timing (Cont'd)
EC-43
Page 593 of 2395

SEF944Y
Without CONSULT-IINBEC0642S03021. Turn ignition switch ªONº and wait at least 1 second.
2. Turn ignition switch ªOFFº and wait at least 10 seconds.
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic ªPRE-CONDITION-
INGº (previously mentioned) are in good order.
5. Turn ignition switch ªOFFº and wait at least 10 seconds.
6. Start the engine and let it idle for at least 30 seconds.
7. Disconnect throttle position sensor harness connector (brown),
then reconnect it within 5 seconds.
8. Wait 20 seconds.
9. Make sure that idle speed is within specifications. If not, the
result will be incomplete. In this case, find the cause of the
problem by referring to the NOTE below.
10. Rev up the engine two or three times. Make sure that idle
speed and ignition timing are within specifications.
ITEM SPECIFICATION
Idle speed 750±50 rpm (in ªPº or ªNº position)
Ignition timing 15ɱ5É BTDC (in ªPº or ªNº position)
NOTE:
If idle air volume learning cannot be performed successfully,
proceed as follows:
1)Check that throttle valve is fully closed.
2)Check PCV valve operation.
3)Check that downstream of throttle valve is free from air
leakage.
4)Adjust closed throttle position switch and reset memory.
(Refer to Basic Inspection, EC-101.)
5)When the above four items check out OK, engine compo-
nent parts and their installation condition are question-
able. Check and eliminate the cause of the problem.
It is useful to perform ªTROUBLE DIAGNOSIS Ð SPECIFI-
CATION VALUEº, EC-136.
6)If any of the following conditions occur after the engine
has started, eliminate the cause of the problem and per-
form ªIdle air volume learningº all over again:
IEngine stalls.
IErroneous idle.
IBlown fuses related to the IACV-AAC valve system.
BASIC SERVICE PROCEDURE
Idle Air Volume Learning (Cont'd)
EC-58
Page 679 of 2395

DIAGNOSTIC PROCEDURENBEC0049
1 INSPECTION START
Start engine.
Is engine running?
YesorNo
Ye s©GO TO 9.
No©GO TO 2.
2 CHECK ECM POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ªOFFº and then ªONº.
2. Check voltage between ECM terminal 43 and ground with CONSULT-II or tester.
SEF291X
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
I10A fuses
IHarness connectors M33, F22
IHarness for open or short between ECM and ignition switch
©Repair harness or connectors.
4 CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 48, 57, 106, 108 and engine ground.
Refer to WIRING DIAGRAM.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit (Cont'd)
EC-144
Page 680 of 2395

5 CHECK POWER SUPPLY-II
1. Disconnect ECM relay.
SEF681UB
2. Check voltage between ECM relay terminals 1, 5 and ground with CONSULT-II or tester.
SEF956Y
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the following.
I7.5A and 10A fuses
IHarness for open or short between ECM relay and battery
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 26 and ECM relay terminal 2.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©Go to ªDTC P1320 IGNITION SIGNALº, EC-499.
NG©GO TO 8.
8 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E1, M1 and M32, F23
IHarness for open or short between ECM relay and ECM
©Repair open circuit or short to ground or short to power in harness or connectors.
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TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit (Cont'd)
EC-145
Page 1873 of 2395
SHA967EE
RHA868H
Check body ground circuit for auto amp. with ignition switch OFF.
Check for continuity between terminal Nos. 32, 14 and body
ground.
Ohmmeter terminal
Continuity
(+) (þ)
32
Body ground Yes
14 (Canada only)
If OK, check auto amp. ground circuit, see below.
IIf NG, check 7.5A fuses (Nos. 11 and 24, located in the fuse
block) and 15A fuses (Nos. 1 and 2, located in the fuse block).
IIf fuses are OK, check for open circuit in wiring harness.
Repair or replace as necessary.
IIf fuses are NG, replace fuse and check wiring harness for
short circuit. Repair or replace as necessary.
NOTE:
If OK, replace auto amp.
If NG, repair or replace harness.
TROUBLE DIAGNOSES
A/C System (Cont'd)
HA-74
Page 1900 of 2395
6 CHECK FAN FEED BACK CIRCUIT
Reconnect auto amp. (LCU) harness connector.
Do approx. 12 volts exist between auto amp. (LCU) harness terminal No. 33 and body ground?
RHA825H
YesorNo
Ye s©GO TO 7.
No©Check power supply circuit and 15A fuses (Nos. 1 and 2, located in the fuse block).
Refer to EL-14, ªWiring Diagram Ð POWER к.
IIf OK, check for open circuit in wiring harness.
Repair or replace as necessary.
IIf NG, replace fuse and check wiring harness for short circuit.
Repair or replace as necessary.
7 CHECK POWER SUPPLY FOR AUTO AMP.
Do approx. 12 volts exist between auto amp. harness terminal No. 34 and body ground?
RHA826H
YesorNo
Ye s©1. Replace auto amp.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
4.
Confirm that blower motor operation is normal.
No©GO TO 10.
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TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-101
Page 1901 of 2395

8 CHECK POWER SUPPLY FOR BLOWER MOTOR
Disconnect blower motor harness connector.
Do approx. 12 volts exist between blower motor harness terminal No. 1 and body ground?
RHA091G
YesorNo
Ye s©GO TO 9.
No©Check power supply circuit and 15A fuses (Nos. 1 and 2, located in the fuse
block).
IIf OK, check for open circuit in wiring harness.
Repair or replace as necessary.
IIf NG, replace fuse and check wiring harness for short circuit.
Repair or replace as necessary.
9 CHECK CIRCUIT CONTINUITY BETWEEN BLOWER MOTOR AND FAN CONTROL AMP.
Disconnect blower motor connector and auto amp. (LCU) connector.
Check circuit continuity between blower motor harness terminal No. 2 and fan control amp. harness terminal No. 3.
RHA472G
OK or NG
OK©Check blower motor. (Refer to HA-103.)
1. If NG, replace blower motor.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
4.
Confirm that blower motor operation is normal.
NG©Repair harness or connector.
TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-102