Mazda B-Series 1997 Workshop Manual page 613

ELECTRONIC IGNITION SYSTEM
Key
OFF
Disconnect coil from coil tee, leave El diagnostic
harness connected to vehicle harness coil
connector
Measure resistance between J7 and J3 at 60
pin breakout box
Is resistance greater than 2k ohms?
Key OFF
Disconnect PCM from vehicle harness connector
Measure resistance between J7 and J3 at 60
pin breakout box
Is resistance greater than 1 O k ohms?
Key OFF
Disconnect coil from coil tee, leave El diagnostic
harness connected to vehicle harness coil
connector
Measure resistance between J7 and J6 at 60
pin breakout box
Is resistance greater than 2k ohms?
Key OFF
Disconnect PCM from vehicle harness connector
Measure resistance between J6 and J7 at 60
pin breakout box
Is resistance areater than 1 O k ohms?
Yes
ACTION
7
STEP
Replace coil pack
INSPECTION
Go to step 17
Yes Replace PCM
Yes Replace coil pack
-r
No
No Go to step 19
T-
Check connectors, repair short in coil circuit to ground
Yes Replace PCM
Key OFF
Disconnect coil from coil tee, leave El diagnostic
harness connected to vehicle harness coil
No
Yes
1
Replace coil pack
Check connectors, repair short in coil circuit to ground
pin breakout box
Is resistance areater than 2k ohms?
connector
Measure resistance between J7 and J10 at 60
Measure resistance between J7 and J10 at 60
short in coil circuit to ground
pin breakout box
Is resistance greater than 1 O k ohms?
No
21
Key OFF
Disconnect PCM from vehicle harness connector
Key ON, engine OFF
Measure voltage between J3 and J7 at 60
pin breakout box
Is voltage less than 0.5 volt?
- -
Key OFF
Disconnect PCM from vehicle harness connector
Key ON, engine OFF
Measure voltage between J6 and J7 at 60
pin breakout box
Is voltaae less than 0.5 volt?
Go to step 21
Yes
No
Yes
No
. .
Key OFF
Disconnect PCM from vehicle harness connector
Replace PCM
Check connectors, repair short in coil circuit to power
Yes
Replace PCM
Replace PCM
Check connectors, repair short in coil circuit to power
Key OFF
1
Yes
1
Replace PCM
Disconnect PCM from vehicle harness connector
Key ON, engine OFF
Measure voltage between J10 and J7 at 60
pin breakout box
Is voltage less than 0.5 volt?
Check connectors, repair short in coil circuit to power
Yes 25 Ignition system is OK
Check other system
Check for spark at all high-tension leads while
cranking
When using the timing light, place the grooved end
as close as possible to the plug boot
Very weak or no flashing may be caused by
a fouled plug
Is spark consistent on all high-tension leads (one
spark per crankshaft revolution)?
- - -
Go to step 26
MGI 097-83