GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2002 🢒 Savana 🢒 Engine 🢒 Engine Controls - 6.5L 🢒 DTC P1218

Circuit Description

The powertrain control module (PCM) uses a calibrated resistor which is mounted internally in the injection pump in order to determine the fuel rates. The resistor value is stored in the PCM memory. If the PCM memory has been disturbed or the PCM has been replaced, the PCM will relearn the resistor value on the next ignition cycle.

Conditions for Running the DTC

The ignition switch is in the ON position.

Conditions for Setting the DTC
    • The PCM currently does not have a valid resistor value.
    • The PCM is unable to read a resistor value.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

Check the loose or damaged terminals at the fuel injector driver. Replace as necessary. Clear the DTC, and cycle the ignition. If the DTC clears, treat the condition as an intermittent.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step determines if there is a problem with the connection at the fuel solenoid driver or a malfunctioning injection pump.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

1

Important: Before clearing the DTCs, use the scan tool Capture Info to save the Freeze Frame/Failure Records for reference. The data in the control module is deleted once the Clear Info function is used.

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Are there any other DTCs set?

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3

  1. Check the connection at the fuel solenoid driver.
  2. Clear the DTC and cycle the ignition.
  3. Start the engine and allow the engine to idle.
  4. Activate the Time Set procedure. The diagnostic will only run when a Time Set procedure is performed.
  5. Exit out of the Time Set procedure.
  6. Select DTC and the Specific DTC function.
  7. Enter the DTC number that was set.

Does the scan tool indicate that this diagnostic ran and passed?

Go to Step 5

Go to Step 4

4

Important: The new injection pump must be timed. Refer to Fuel Injection Pump Timing Adjustment .

Replace the fuel injection pump. Refer to Fuel Injection Pump Replacement .

Did you complete the replacement?

Go to Step 6

--

5

The DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored, refer to those tables.

Are any additional DTCs stored?

Go to Diagnostic Trouble Code (DTC) List

Go to Diagnostic Aids

6

Operate the vehicle under the conditions for running and setting.

Does the scan tool indicate the diagnostic has passed?

Go to Step 7

Go to Step 2

7

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK