Mazda MX-6 1998, Workshop Manual

Page: 115 / 1282

TROUBLESHOOTING [ENGINE CONTROL FS]
STEP
INSPECTION ACTION
6 RETRIEVE ANY CONTINUOUS MEMORY
DTCs
Note
• If failures are present in the following
components or systems, this could cause
PCM to complete KOER self-test and/or
cause PCM to generate NGS tester
communication error message:
0 Idle speed control
© EGR system
© Fuel control system
@ Vehicle speed sensor circuits
© Mass air flow sensor circuits
© T ra n s a x le range switch circuits
Note
• For information on retrieving MIL and
non-MIL DTCs, continuous memory
self-test.
• NGS tester connected.
• Key on, engine off.
• Retrieve and record all Continuous Memory
DTCs (MIL and non-MIL).
• Key off.
• Were any Continuous Memory DTCs
present.
Yes Go to appropriate DTC chart.
No Go to step 7.
7
CHECK POWER CIRCUIT AT DLC
• Key off.
• Inspect the DLC for damage. Service as
necessary.
• Measure voltage between power circuit
cavity at DLC and engine block ground.
• Is voltage greater than 10.5 volts?
Yes Go to next step.
No SERVICE open in DLC power circuit.
RERUN OBD Test.
8
CHECK DLC CHASSIS GROUND
CONTINUITY
• Key off.
• Measure resistance between chassis
ground circuit cavity at DLC and chassis
ground.
• Is resistance less than 5.0 ohms?
Yes Go to next step.
No
SERVICE open in DLC chassis ground circuit.
RERUN OBD Test.
9 CHECK DLC GROUND CIRCUIT
CONTINUITY
• Key off.
• Disconnect PCM. Inspect for damaged or
pushed out pins, loose wires, corrosion,
etc. Service as necessary.
• Install breakout box. Leave PCM
disconnected.
• Disconnect NGS tester.
• Measure resistance between Test Pin 51 or
103 at breakout box and ground circuit
cavity at DLC.
• Is resistance less than 5.0 ohms?
Yes Go to next step.
No SERVICE open in DLC ground circuit.
RECONNECT PCM.
REMOVE breakout box.
RERUN OBD Test.
10
CHECK DLC B U S (-) CIRCUIT CONTINUITY
• Key off.
• Breakout box installed. Leave PCM
disconnected.
• Measure resistance between Test Pin 15
B U S (-) at breakout box and BUS(-) circuit
at DLC.
• Is resistance less than 5 ohms?
Yes
Go to next step.
No SERVICE open in DLC B U S (-) circuit.
RECONNECT PCM.
REMOVE breakout box.
RERUN OBD Test.
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