The crankshaft position
system variation compensating values are stored in the PCM non-volatile memory
after a learn procedure has been performed. If the actual
crankshaft position system variation is not within
the crankshaft
position system variation compensating values stored in the PCM,
DTC P0300 may set (refer to Diagnostic Aids for DTC P0300).
The Crankshaft Position System Variation Learn Procedure should be performed
if any of the following conditions are true:
| • | The PCM has been replaced. |
| • | The engine has been replaced. |
| • | The crankshaft has been replaced. |
| • | The crankshaft harmonic balancer has been replaced. |
| • | The crankshaft position sensor has been replaced. |
Caution: Before performing the Crankshaft Position System Variation Learning
Procedure always set the vehicle parking brake and block the drive wheels
in order to prevent personal injury. Release the throttle immediately when
the engine starts to decelerate in order to eliminate over revving the engine.
Once the learn procedure is completed, the control module will return engine
control to the operator and the engine will respond to the throttle position.
Important: The scan tool crankshaft position system variation learn function will
be inhibited if engine coolant temperature is less than 70°C
(158°F).
Allow the engine to warm to at least 70°C
(158°F) before attempting
the crankshaft position system
variation learn procedure.
The scan tool crankshaft position system variation learn function will
be inhibited if any powertrain DTCs other than DTC P1336
are set before or
during the crankshaft position system variation
learn procedure. Diagnose
and repair any DTCs if set.
The crankshaft position system variation learn function will be inhibited
if the PCM detects a malfunction involving the camshaft position
signal circuit,
the 3X reference circuit, or the 24X reference
circuit.
The scan tool crankshaft position system variation learn function will
not be enabled until engine coolant temperature is greater
than 70°C
(158°F).
Selecting the crankshaft position variation learn procedure on the
scan tool will command the PCM to enable CKP system variation
learn cut-OFF
and allow the crankshaft position system compensating
values to be stores in
the PCM. The PCM must be detect an engine
speed of 5150 rpm (CKP system variation
learn fuel cutoff)
during the crankshaft position system variation learn procedure
to
store the crankshaft position system compensating values and
complete the
procedure.
- Set the parking brake.
- Block the drive wheels.
- Ensure the hood is closed.
- Start the engine and allow engine coolant temperature to reach
at least 70°C (158°F).
- Turn OFF the ignition switch.
- Select and enable the crankshaft position variation learn procedure
with the scan tool
- Start the engine.
- Apply and hold the service brake pedal firmly.
- Ensure the transaxle is in park.
- Increase accelerator pedal position until CKP system variation
learn fuel cutoff is reached. CKP system variation learn fuel
cutoff is reached
at 5150 rpm. Immediately release the accelerator
pedal when fuel cutoff is
reached.
- The crankshaft position system variation compensating values are
learned when the rpm decreases back to idle.
- Observe DTC status for DTC P1336.
- If the scan tool indicates that DTC P1336 ran and passed,
the crankshaft position system variation learn procedure is complete.
If the scan tool indicates DTC P1336
failed or not run, check for other DTCs. If no DTCs
other than P1336 are set, repeat the crankshaft position
system variation learn procedure as necessary.
