Mazda 626 Station Wagon, Workshop Manual

Page: 131 / 577

TROUBLESHOOTING
STEP
INSPECTION RESULTS ACTION
6 Does immobilizer indicator light flash and
indicate either of following immobilizer system
DTCs more than 135 seconds after ignition
switch is turned on?
DTC: 24, 30
Yes Go to “ON-BOARD DIAGNOSTIC FUNCTION"
of immobilizer system.
No Go to next step.
7 Turn ignition switch off.
Disconnect immobilizer unit connector.
Connect jumper wire between immobilizer unit
connector terminal M and GND.
Turn ignition switch on.
Does immobilizer indicator light illuminate?
Yes Reconnect immobilizer unit connector.
Go to next step.
No
Inspect for open circuit between immobilizer unit
connector terminal M and instrument cluster.
If okay, inspect immobilizer indicator light bulb.
Repair or replace if necessary. Reconnect
immobilizer unit connector, then return to Step 4.
8 Connect NGS tester to DLC and retrieve DTC.
Are any of following DTCs displayed?
DTC: P1602, P1603, P1604, P1621, P1622,
P1624
Yes Go to appropriate DTC test.
No Go to next step.
9
Is there continuity between PCM GND terminals
24, 51, 76, 77,103 and GND?
Yes Go to next step.
No
Repair or replace wiring harness.
10 Turn ignition switch on.
Access B+ PID.
Is B+ or VPWR PID okay?
B+ (VPWR) PID: Battery voltage
Yes Go to next step.
No Repair or replace wiring harness.
11 Disconnect immobilizer unit connector.
Turn ignition switch on.
Is there battery voltage at immobilizer unit
connector terminal J?
Yes
Inspect for open circuit between PCM connector
terminal 5 (for GF4A-EL models) or 66 (except
for GF4A-EL models) and immobilizer unit
connector terminal A.
No Repair or replace wiring harness between
immobilizer unit connector terminal J and fuse
panel.
12
Verify following:
• Vacuum connection
• Air cleaner element
• No air leakage from intake-air system
• No restriction of intake-air system
• Proper sealing of intake manifold and
components attached to intake manifold (e.g.
EGR valve, IAC valve.)
• Ignition wiring
• Fuel quality (e.g. proper octane,
contamination, winter/summer blend)
• Electrical connections
• Smooth operation of throttle valve
Are all items okay?
Yes
r Go to next step.
No Service as necessary.
Repeat Step 12.
13 Turn ignition switch on.
Disconnect TP sensor connector.
Measure voltage at TP sensor connector VREF
terminal with ignition switch on.
Voltage: 4.5—5.5 V
Is voltage okay?
Yes Go to next step.
No Go to symptom troubleshooting No.27 “Constant
voltage”.
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