Page 65 of 192

Main Power Supply and Ground Circuit
ECM TERMINALS AND REFERENCE VALUE
Remarks: Speci®cation data are reference values and are measured between each terminal andV43(ECCS
ground) with a voltmeter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
4 B/Y ECCS relay (Self-shutoff)Ignition switch ``ON''
Ignition switch ``OFF''
For a few seconds after turning ignition switch
``OFF''0 - 1.5V
Ignition switch ``OFF''
A few seconds passed after turning ignition
switch ``OFF''BATTERY VOLTAGE
(11 - 14V)
38 B/Y Ignition switchIgnition switch ``OFF''
0V
Ignition switch ``ON''
BATTERY VOLTAGE
(11 - 14V)
39
43B ECCS groundEngine is running.
Idle speedEngine ground
(Probe this terminal with
@tester probe when
measuring.)
56
61W Power supply for ECM Ignition switch ``ON''
BATTERY VOLTAGE
(11 - 14V)
70 BR Power supply (Back-up) Ignition switch ``OFF''
BATTERY VOLTAGE
(11 - 14V)
106
11 2
11 8B ECCS groundEngine is running.
Idle speedApproximately 0V
11 6
11 7W Power supply for ECM Ignition switch ``ON''
BATTERY VOLTAGE
(11 - 14V)
TROUBLE DIAGNOSIS FOR POWER SUPPLY
EC-63
Page 66 of 192
TEC421
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit
(Cont'd)
EC-64
Page 67 of 192
TEC422
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit
(Cont'd)
EC-65
Page 68 of 192

INSPECTION START
Start engine.
Is engine running?
Ye s
cNo
CHECK POWER SUP-
PLY-I.
1. Turn ignition switch
``ON''.
2. Check voltage between
ECM terminal
V38and
ground with CONSULT
or tester.
Voltage: Battery volt-
age
If NG, check the following.
+Harness connectors
M51,F6+10A fuse
+Harness for open or
short between ECM and
fuse
If NG, repair harness or
connectors.
OK
Go to
``CHECK
GROUND CIRCUIT'' on
EC-68.
CHECK POWER SUPPLY-II.
1. Stop engine.
2. Check voltage between ECM terminal
V70and ground with CONSULT or
tester.
Voltage: Battery voltage
OK
cNG
Check the following.
+Harness connectors
E127,M21+Harness connectorsM52,F7+7.5A fuse
+Harness for open or
short between ECM and
battery
If NG, repair harness or
connectors.
CHECK POWER SUPPLY-III.
1. Turn ignition switch ``ON'' and then
``OFF''.
2. Check voltage between ECM terminals
V56,V61,11 6,11 7and ground with
CONSULT or tester.
Voltage:
After turning ignition switch ``OFF'',
battery voltage will exist for a few
seconds, then drop to approximately
0V.
NG
cOK
Go to``CHECK
GROUND CIRCUIT'' on
EC-68.
Case-1: Battery voltage does
not exist.
Case-2: Battery voltage exists
for more than a few
seconds.
Case-1
cCase-2
Go to``CHECK ECCS
RELAY'' on next page.
jA
SEF065P
SEF056R
SEF566S
SEF567S
.
.
.
.
.
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit
(Cont'd)
EC-66
Page 69 of 192

jA
CHECK HARNESS CONTINUITY
BETWEEN ECCS RELAY AND ECM.
1. Disconnect ECM harness connector.
2. Disconnect ECCS relay.
3. Check harness continuity between ECM
terminals
V56,V61and relay terminal
V7, and ECM terminals11 6,11 7
and relay terminalV5.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Check the following.
+Harness connectors
M52,F7
+Harness connectors
M50,F5
+Harness for open or
short between ECM and
ECCS relay
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK VOLTAGE BETWEEN ECCS
RELAY AND GROUND.
Check voltage between relay terminals
V1,V3,V6and ground with CONSULT
or tester.
Voltage: Battery voltage
OK
cNG
Check the following.
+Harness connectors
E127,M21
+15A fuse
+Harness for open or
short between ECCS
relay and battery
If NG, repair harness or
connectors.
CHECK OUTPUT SIGNAL CIRCUIT.
Check harness continuity between ECM
terminal
V4and relay terminalV2.
Continuity should exist.
If OK, check harness for short to ground
and short to power.
OK
cNG
Check the following.
+Harness connectors
M52,F7
+Harness for open or
short between ECM and
ECCS relay
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
CHECK ECCS RELAY.
1. Apply 12V direct current between relay
terminals
V1andV2.
2. Check continuity between relay termi-
nals
V3andV5,V7andV6.
12V (
V1-V2) applied:
Continuity exists.
No voltage applied:
No continuity
OK
cNG
Replace ECCS relay.
jB
SEF513V
SEF569S
SEF030S
SEC202B
.
.
.
.
.
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit
(Cont'd)
EC-67
Page 70 of 192
jB
CHECK GROUND CIRCUIT.
1. Turn ignition switch ``OFF''.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM
terminals
V39,V43,106,11 2,11 8
and engine ground.
Continuity should exist.
If OK, check harness for short to
ground and short to power.
OK
cNG
Check the following.
+Joint connector
F18
+Harness for open or
short between ECM and
ground
If NG, repair open circuit or
short to ground or short to
power in harness or con-
nectors.
Check ECM pin terminals for damage and
check the connection of ECM harness
connector.
INSPECTION END
SEF570S
.
.
.
TROUBLE DIAGNOSIS FOR POWER SUPPLY
Main Power Supply and Ground Circuit
(Cont'd)
EC-68
Page 71 of 192

Camshaft Position Sensor (CMPS) (PUMP)
The camshaft position sensor (PUMP) is located on the electronic
fuel injection pump.
The sensor consists of a permanent magnet, core and coil.
When engine is running, gap between sensor and drive shaft rotat-
ing plate will periodically change. Permeability near the sensor also
changes.
Due to the permeability change, the magnetic ¯ux near the core is
changed. Therefore, the voltage signal generated in the coil is
changed.
The ECM receives the voltage signal (6 pulses/2 engine revolu-
tions).
These signals are used for tachometer indication.
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Speci®cation data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
CKPSzRPM (REF)+Tachometer: Connect
+Run engine and compare tachometer indication with the CONSULT
value.Almost the same speed as the
CONSULT value.
CKPSzRPM-PUMP
ECM TERMINALS AND REFERENCE VALUE
Remarks: Speci®cation data are reference values and are measured between each terminal andV43(ECCS
ground) with a voltmeter.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
28
33BCamshaft position sensor
(PUMP) groundEngine is running.
(Warm-up condition)
Idle speedApproximately 0V
41
45WCamshaft position sensor
(PUMP)Engine is running.
(Warm-up condition)
Idle speedApproximately 0V
SEF722V
Engine is running.(Warm-up condition)
Engine speed is 2,000 rpm.Approximately 0V
SEF723V
SEF674V
TROUBLE DIAGNOSIS FOR ``CAM POS SEN (PUMP)'' (DTC 11)
EC-69
Page 72 of 192

ON BOARD DIAGNOSIS LOGIC
Diagnostic
Trouble Code
No.Malfunction is detected when ....Check Items
(Possible cause)
11+An improper signal from the sensor is detected by
ECM during engine running.+Harness or connectors
[The camshaft position sensor (PUMP) circuit is open
or shorted.]
+Camshaft position sensor (PUMP)
DIAGNOSTIC TROUBLE CODE CONFIRMATION
PROCEDURE
1) Turn ignition switch ``ON'' and select ``DATA MONITOR''
mode with CONSULT.
2) Start engine and run it for at least 2 seconds at idle
speed.
(If engine does not run, turn ignition switch to ``START''
for at least 2 seconds.)
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------OR-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1) Start engine and run it for at least 2 seconds at idle
speed.
(If engine does not run, turn ignition switch to ``START''
for at least 2 seconds.)
2) Turn ignition switch ``OFF'', wait at least 5 seconds and
then ``ON''.
3) Perform ``Diagnostic Test Mode II (Self-diagnostic
results)'' with ECM.
SEF714V
TROUBLE DIAGNOSIS FOR ``CAM POS SEN (PUMP)'' (DTC 11)
Camshaft Position Sensor (CMPS) (PUMP)
(Cont'd)
EC-70