Mazda MX-6 1998, Workshop Manual

Page: 312 / 1282

TROUBLESHOOTING [ENGINE CONTROL KL]
STEP
INSPECTION ACTION
12 CHECK EGR BOOST SENSOR SIGNAL
CIRCUIT FOR SHORT TO GROUND AND
POWER
• Key off.
• EGR boost sensor disconnected.
• Breakout box installed. PCM disconnected.
• Measure resistance between Test Pin 34
and test Pin 91, 51 and 103 at breakout
box.
• Measure resistance between Test pin 34
and Test Pin 71, 90 and 97 at breakout
box.
• is resistance greater than 10,000 ohms?
Yes Go to next step.
No SERVICE short in EGR boost sensor signal circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
S
3
» After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
Confirm repair by performing by EGR portion of OBD II
Drive Mode to check for DTCs.
13
CHECK EGR VALVE POWER CIRCUIT
VOLTAGE
• Key off.
• Disconnect EGR valve.
• Key on, engine off.
• Measure voltage between power circuit at
EGR valve harness connector C or D and
battery negative post.
• Is each voltage greater than 10.5 volts?
Yes
Power harness circuit from main relay to EGR is okay.
Go to next step.
No SERVICE open power circuit.
Reconnect all components.
RESET PCM to completely clear DTCs.
c r After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
Confirm repair by performing by EGR portion of OBD II
Drive Mode to check for DTCs.
14
CHECK EGR CONTROL SIGNAL CIRCUIT
SHORT TO GROUND
• Key off.
• EGR valve disconnected.
• Disconnect PCM.
• Measure resistance between following
terminals EGR valve connector and battery
negative post.
• Test Pin 68
• Test Pin 72
• Test Pin 46
• Test Pin 56
•
Is each resistance greater than 10,000
ohms?
Yes EGR valve control signal harness circuit to PCM is okay.
Go to next step.
No SERVICE short circuit between EGR valve control signal
circuit.
RESET PCM to completely clear DTCs.
¡nr After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
Confirm repair by performing by EGR portion of OBD II
Drive Mode to check for DTCs.
15
CHECK CONTINUITY EGR VALVE
CONTROL SIGNAL CIRCUIT OPEN
• Key off.
• EGR valve disconnected.
• Breakout box installed. PCM disconnected.
• Measure voltage between appropriate Test
Pin at breakout box and EGR valve
terminal at harness connector.
• EGR valve terminal E-Test Pin 68
• EGR valve terminal A-Test Pin 72
• EGR valve terminal B-Test Pin 46
• EGR valve terminal F-Test Pin 56
•
Is each resistance less than 5.0 ohms?
Yes EGR valve control signal circuits are okay.
Service EGR valve.
C7- 0 1 -1 6A EGR VALVE INSPECTION [FS]
No SERVICE open in EGR valve control signal circuit
harness.
RECONNECT all components.
RESET PCM to completely clear DTCs.
cs“ After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
Confirm repair by performing by EGR portion of OBD II
Drive Mode to check for DTCs.
0 1 -0 1 B -1 06