DTC P1218 Injection Pump Calibration Circuit. GMC Truck Yukon

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 1997 🢒 Yukon - 4WD 🢒 Engine 🢒 Engine Controls - 6.5L 🢒 DTC P1218 Injection Pump Calibration Circuit

Refer to

DIESEL PCM, FUEL SOLENOID, WATER IN FUEL

Engine Controls Components
DIESEL PCM, CKP, FUEL TEMP, ITS
DIESEL FUEL PUMP, LIFT PUMP
OBD II Symbol Description Notice
Engine Controls Schematic References
Engine Controls Schematic References
Engine Controls Schematic References
Handling Electrostatic Discharge Sensitive Parts Notice
Handling Electrostatic Discharge Sensitive Parts Notice
Engine Controls Schematic References
Engine Controls Schematic References
Engine Controls Schematic References

Circuit Description

The PCM uses a calibrated resistor mounted internally in the injection pump to determine 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. This is a type B DTC.

Conditions for Setting the DTC

•	PCM currently does not have a valid resistor valve.

•	PCM is unable to read a resistor value

Action Taken When the DTC Sets

The lowest fuel table. Possible poor performance problem.

Conditions for Clearing the MIL/DTC

•	The PCM will turn the MIL off after three consecutive trips without a fault condition.

•	A History DTC will clear when forty consecutive warm-up cycles that the diagnostic does not fail (coolant temperature has risen 5°C (40°F) from start up coolant temperature and engine coolant temperature exceeds 71°C (160°F) that same ignition cycle.

•	Use of a Scan Tool

Diagnostic Aids

Check connection at fuel injector driver. Clear DTC, and cycle ignition. If DTC clears, treat condition as an intermittent.

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

This step will determine if there is a problem with the connection at the fuel solenoid driver or malfunctioning injection pump. This DTC will only clear DTC Status when a Time Set procedure has been activated (injection timing does not have to be adjusted).

Step	Action	Value(s)	Yes	No
1	Important: Before clearing DTCs use the scan tool Capture Info to record freeze frame and failure records for reference, as data will be lost when Clear Info function is used. Was the Powertrain On-Board Diagnostic (OBD) System Check performed?	--	Go to Step 2	Go to Powertrain On Board Diagnostic (OBD) System Check
2	Are than any other DTCs set?	--	Refer to Applicable DTC Table	Go to Step 3
3	Check connection at Fuel Solenoid Driver. Clear DTC, and cycle ignition. Start and idle engine. Activate Time set procedure (the diagnostic will only run when a Time Set procedure is performed). Exit out of Time set procedure and Select DTC, Specific, then enter the DTC number. Does the Scan Tool indicate that the diagnostic Passed?	--	Go to Step 5	Go to Step 4
4	Replace injection pump. Important: The new injection pump must be timed. Refer to Fuel Injection Pump Replacement . Is the action complete?	--	Go to Step 6	--
5	DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored refer to those table(s). Are any additional DTC(s) stored?	--	Go to the Applicable DTC Table	Go to Diagnostic Aids
6	Using the Scan Tool, select Capture Info, Review Info. Are any DTCs displayed that have not been diagnosed?	--	Go to the Applicable DTC Table	System OK