Mazda 626 Station Wagon, Workshop Manual

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ON-BOARD DIAGNOSTIC
jDTC P0103
Except for GF4A-EL Models
DTC P0103
MAF circuit high input
DETECTION
CONDITION
• PCM monitors input voltage from MAF sensor when engine speed is below 4100 rpm. If input voltage
at PCM terminal 88 is above 4.3 V, PCM determines that MAF circuit has a malfunction.
POSSIBLE
CAUSE
• MAF sensor malfunction
• Connector or terminal malfunction
• Open circuit in wiring between MAF sensor terminal D and PCM terminal 36
MAF SENSOR
FROM MAIN RELAY
TERMINAL D
PCM
<5
h©
0
» ■
0 — I
T77- 777-
MAF SENSOR
3 6
PCM
{VIEW FROM TERMINAL SIDE)
(VIEW FROM TERMINAL SIDE)
Diagnostic procedure
STEP INSPECTION ACTION
1 VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Information
availability.
• Is any related Service Information available?
Yes Perform repair or diagnosis according to available
Service Information.
• If vehicle is not repaired, then go to next step.
No Go to next step.
2 VERIFY CURRENT INPUT SIGNAL STATUS -
IS CONCERN INTERMITTENT OR CONSTANT
• Connect NGS tester to DLC
• Start engine.
• Access MAF V PID using NGS tester.
• Is MAF V PID
below
4.3 V?
Yes Intermittent concern is existing. Go to
INTERMITTENT CONCERN TROUBLESHOOTING
procedure.
(See F1-142 No.26 INTERMITTENT CONCERNS)
No Go to next step.
3
INSPECT POOR CONNECTION OF MAF
SENSOR CONNECTOR
• Turn ignition key to OFF.
• Disconnect the MAF sensor connector.
• Check for poor connection (damaged,
pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes Repair or replace terminals, then go to Step 7.
No Go to next step.
F1-43