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
no be enabled until engine coolant temperature reaches 70°C (158°F).
Selecting the crankshaft position system variation learn procedure on
the scan will command the PCM to enable CKP system variation learn fuel cutoff
and allow the crankshaft position system variation compensating values
to be stored in the PCM. The PCM must 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
variation 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 vehicle.
- Apply and hold the brake pedal firmly.
- Ensure the transaxle is in park.
- Increase accelerator pedal position until the fuel cutoff is
reached at 5150 rpm. Immediately release the accelerator pedal after fuel
cutoff is reached.
- The crankshaft position system variation compensating values
are learned when the rpm decreases back to idle. If the procedure terminates.
- 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.
