TEST
ACTION
APPLICABILITY
13
Turn the ignition off.
With the DRBIII
t lab scope, back probe the CMP signal circuit at the PCM harness
connector using Miller special tool #6801.
Warning: Keep clear of the engine’s moving parts.
Start the engine.
Observe the lab scope screen while wiggling the wiring harness and connectors
related to the CMP sensor.
Were there any irregularities in the lab scope pattern when the wiggle test was
conducted?
All
Yes
→
Note where wiggling caused a missing CMP sensor signal. Repair
CMP sensor wiring as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Test Complete.
14
Turn the ignition off.
Connect the DRBIII
t lab scope to the CMP signal circuit. For best results, back probe
at the PCM harness connector using Miller special tool #6801.
WARNING: Keep clear of the engine’s moving parts.
Start the engine.
Observe the lab scope screen while wiggling the wiring harness and connectors.
Were there any irregularities in the lab scope pattern?
All
Yes
→
Check harness and connectors carefully. If OK, replace the
Camshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Go To
15
15
Turn ignition off.
Visually inspect the related wiring harness. Look for any chafed, pierced,
pinched, or partially broken wires.
Visually inspect the related wire harness connectors. Look for broken, bent,
pushed out, or corroded terminals.
Note: Refer to any technical service bulletins that may apply.
Were any problems found?
All
Yes
→
Repair wiring harness/connectors as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Go To
16
16
Turn the ignition off.
Connect the DRBIII
t lab scope to the CKP signal circuit. For best results, back probe
at the PCM harness connector using Miller special tool #6801.
Warning: Keep clear of the engine’s moving parts.
Start the engine.
Observe the lab scope screen while wiggling the wiring harness and connectors.
Were there any irregularities in the lab scope pattern?
All
Yes
→
Check harness and connectors carefully. If OK, replace the
Crankshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→
Test Complete.
221
DRIVEABILITY - GAS
P1391-INTERMITTENT LOSS OF CMP OR CKP —
Continued