Mazda MX-6 1998, Workshop Manual

Page: 46 / 1282

TROUBLESHOOTING [ENGINE CONTROL FS]
STEP INSPECTION
ACTION
9 CHECK EGR BOOST SOLENOID CIRCUIT
FOR SHORT TO POWER AND GROUND
•
Key off.
•
EGR boost solenoid disconnected.
•
Breakout box installed, PCM disconnected.
•
Measure resistance between Test Pin 98
and Test Pins 71, 97 and 90 at breakout
box.
• Measure resistance between Test Pin 98
and Test Pins 51, 103 and 91 at breakout
box.
• Is each resistance greater than 10,000
ohms?
Yes
REMOVE breakout box.
RECONNECT all components.
Go to next step.
No
SERVICE short in EGR boost solenoid harness circuit.
REMOVE breakout box.
RECONNECT all components.
RESET PCM to completely clear DTCs.
p*
After Repair Procedure
COMPLETE OBD II Drive Mode.
Confirm repair by performing EGR portion of OBD II Drive
Mode to check for DTCs.
10 CHECK EGR BOOST SOLENOID VALVE
OPERATION
® Key off.
•
Breakout box installed. PCM connected.
•
Disconnect the vacuum line from intake
manifold vacuum reservoir to EGR boost
solenoid at EGR boost solenoid.
•
Install vacuum pump at input port of EGR
boost solenoid, apply -2 7 ------33 kPa
{-2 0 3 ----- 254 mmHg, - 8 ------10 inHg} of
vacuum to EGR boost solenoid.
•
Disconnect vacuum line from barometric
pressure to EGR boost sensor at
Barometric Pressure Sensor install vacuum
gauge at unattached end of vacuum line.
•
Key on.
•
Momentarily jumper to ground Test Pin 98
at breakout box to ground and observe the
vacuum gauge.
•
Key off.
•
Was vacuum signal of 0
-----
3.3 kPa {0
—
-2 5 mmHg, 0------1 inHg} indicated by the
vacuum gauge before Test Pins 98 and
51 were shorted and -2 7 ------33 kPa
{-2 0 3 ------254 mmHg, - 8 ------10 inHg}
after Pins were shorted?
Yes REPLACE damaged PCM.
REMOVE breakout box.
REMOVE vacuum gauge and vacuum pump.
RECONNECT all components.
RESET PCM to completely clear DTCs.
c? After Repair Procedure
COMPLETE OBD II Drive Mode.
Confirm repair by performing EGR portion of OBD II Drive
Mode to check for DTCs.
No REPLACE damaged EGR boost solenoid.
REMOVE breakout box.
REMOVE vacuum gauge and vacuum pump.
RECONNECT all components.
RESET PCM to completely clear DTCs.
zt
After Repair Procedure
COMPLETE OBD II Drive Mode.
Confirm repair by performing EGR portion of OBD II Drive
Mode to check for DTCs.
0 1 -0 1 A - 1 8