Subject: | MIL (SERVICE ENGINE SOON Telltale Lamp) On with DTC P0300 and Possible Pairs
of DTCs P0301 and P0304, and/or P0302 and P0303 in PCM memory (Relearn Crankshaft
Adaptives) |
Condition
Malfunction indicator lamp (MIL) (SERVICE ENGINE SOON telltale lamp) On with
driveability complaints. Diagnostic trouble code (DTC) P0300 in PCM memory, possibly
with pairs of the following DTCs: P0301 and P0304, and/or P0302 and P0303.
Cause
Possible inaccurately learned crankshaft characteristics.
Correction
Using a Scan tool or the Saturn service stall system (SSS), inspect for DTCs.
If any DTCs other than the misfire DTCs are present, or if any misfires can be felt
in the engine, refer to diagnostic procedures in the "1996 Powertrain Controls
Service Manual."
Using the Scan tool or SSS, display the misfire table. If equal number of misfires
are registered by cylinder pairs 1 and 4, and/or 2 and 3, then the crankshaft profile
may have been inaccurately learned.
• | Follow the procedure in this bulletin to relearn crankshaft adaptives. |
• | If misfires are not registered equally in cylinder pairs, refer to the
diagnostic procedures in the "1996 Powertrain Controls Service Manual." |
Procedure
Reset and Relearn Crankshaft Adaptives using the following
Procedure (Using the Service Stall System):
- Key On, Engine Off.
- Identify the Vehicle
- Select Dynamic Display (#3) from the Main Menu
- Select View Serial Data (#1)
- Select PCM/EC (#1)
- Record and clear all diagnostic trouble codes (DTCs)
6.1. | Select General Information (#1) |
6.2. | Press F8 to select Trouble Codes |
6.3. | Capture all information on non-misfire DTCs. (Refer to "1996 Powertrain
Controls Service Manual.") |
6.4. | Press F5 to Clears Codes (button of screen) |
6.5. | Press ESC (escape) (return to previous menu) |
• | Select Vehicle ID Table (#2) |
• | Press F7 to select Reset Adaptives (button of screen) |
• | Turn the ignition key Off for ten seconds. |
• | Start the engine and allow it to idle. The Service (Wrench) telltale will
begin to flash. |
• | Raise and hold engine speed to between 3000 and 4000 RPM until Service
(Wrench) telltale goes out (approximately 10 seconds). If the Service (Wrench) telltale
has not turned Off after more than 10 seconds, a misfire is still present and must
be diagnosed before the crankshaft can be relearned. |
• | After resetting crankshaft adaptives, the misfire table should be selected
on Scan tool or the SSS. View the status of the crank learned parameter. The parameter
should be switched to YES if the crank has been learned successfully. If not, repeat
above steps. Watch the misfire tables for additional counts to verify the repair.
If additional counts are present, follow the diagnostics in the "1996 Powertrain
Controls Service Manual." |
Claim Information
To receive credit for this during the warranty coverage period, submit a claim
through the Saturn Dealer System using the appropriate Electronic Labor Time Guide
and Labor Operation Code J6365 (Crankshaft Relearn).