GM Service Manual Online
For 1990-2009 cars only

Object Number: 29541  Size: MF
Handling ESD Sensitive Parts Notice
Engine Controls Components
Crankshaft Position, Optical/Fuel Temperature Sensor, and Injection Timing Stepper Motor
OBD II Symbol Description Notice

Circuit Description

Timing of the combustion event is accomplished by delivering a pulse of fuel into the combustion chamber at a desired degree of cylinder travel. This desired degree (desired timing), defines the current position of the cylinder in relationship of Top Dead Center. This test compares desired timing to measured timing when certain conditions have been met. To retard injection timing the PCM extends the Stepper motor. To advance injection timing the PCM retracts the Stepper motor. This is a type B DTC.

Conditions for Setting the DTC

    • Engine speed has not changed more than 56 rpm for 20.8 seconds.
    • A 5 degree deference between Act. Inj. Time and Des. Inj. Time

Action Taken When the DTC Sets

Possible combustion noise.

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

A hard start and possible poor performance condition might exist. Act. Inj. Time will freeze at the point of the fault. Its possible DTC P0216 will set if injection timing is not set correctly. Refer to Checking and Adjusting Injection Timing for correct procedure.

Test Description

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

  1. This Step determines if DTC P0216 is a hard failure or an intermittent.

  2. This Step checks for an open or short in the injection timing coil circuit 1.

  3. This Step checks for an open or short in the injection timing coil circuit 2.

  4. The important thing in this Step is that the PCM is sending a varying voltage (voltage may vary between 1 and 12 (usually you will see voltage vary between 5 and 6 when engine is idling)), this will indicate that the PCM is OK and that there is a problem with the injection timing Stepper motor. If there is a steady voltage present on any circuit, this will indicate a problem with the PCM or a circuit shorted to voltage.

DTC P0216 Injection Timing Control System

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 On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to OBD System Check

2

  1. Engine at operating temperature.
  2. Scan injection timing at idle and at 2700 RPM.

Does scan tool display a difference greter then or equal to the specified value between Actual Inj Time and Desired Inj Time at idle or at 2700 RPMs?

Go to Step 4

Go to Step 3

3

DTC is intermittent. If no additional DTCs are stored, refer to Diagnostic Aids. If additional DTCs were stored refer to those table(s) first. Are additional DTCs stored?

--

Go to thepplicable DTC Table

Go to Diagnostic Aids

4

  1. Ignition OFF.
  2. Disconnect PCM.
  3. Measure resistance between coil 1 low and coil 1 high at PCM harness.

Is resistance between specified value?

10 - 60 Ohms

Go to Step 5

Go to Step 9

5

Measure resistance between coil 2 low and coil 2 high at PCM harness.

Is resistance between specified value?

10 - 60 Ohms

Go to Step 6

Go to Step 10

6

  1. Reconnect PCM.
  2. Disconnect Injection Timing Stepper motor.
  3. Start and idle engine.
  4. Using scan tool, command Time Set ON.
  5. With J 39200 connected to ground, check for a varying voltage on all terminals at injection timing Stepper motor electrical harness.

Does voltage vary (all circuits)?

--

Go to Step 7

Go to Step 12

7

  1. Disconnect crankshaft position sensor.
  2. At sensor pigtail, measure resistance between crankshaft position sensor signal and 5 volt reference circuit .

Is resistance between specified value?

950 -1050

Ohms

Go to Step 8

Go to Step 13

8

  1. Reconnect the crankshaft position sensor and check for one of the following:
  2. • Injection timing set correctly. Refer to Checking and Adjusting Injection Timing.
    • Sheared camshaft driven key. Refer to Engine Mechanical.
  3. If a problem is found, repair it as necessary.

Was a repair performed?

--

Go to Step 18

Go to Step 16

9

  1. Ignition OFF.
  2. Disconnect the injection timing stepper motor and check for an open or short in the following:
  3. • Coil 1 low circuit.
    • Coil 1 high circuit.
    • If a problem is found, repair it as necessary.

Was a repair performed?

--

Go to Step 18

Go to Step 11

10

  1. Ignition OFF.
  2. Disconnect the injection timing stepper motor and check for an open or short in the following: :
  3. • Coil 2 low circuit.
    • Coil 2 high circuit.
    • If a problem is found, repair it as necessary.

Was a repair performed?

--

Go to Step 18

Go to Step 11

11

Check for poor electrical connection at the injection timing Stepper motor.

Did any terminals require replacement?

--

Go to Step 18

Go to Step 16

12

Check the circuit for a short to ground or a poor connection at the PCM.

Was a repair performed?

--

Go to Step 18

Go to Step 17

13

  1. Check crankshaft sensor pigtail for a short to ground.
  2. If the circuit is shorted to ground, repair it as necessary.

Was a repair performed?

--

Go to Step 18

Go to Step 14

14

Check the circuit for a poor connection and replace terminal if necessary.

Did the terminal require replacement?

--

Go to Step 18

Go to Step 17

15

Replace crankshaft position sensor. Refer to Crankshaft Position Sensor Replacement

Is the action complete?

--

Go to Step 18

--

16

Replace Injection pump. Refer to Fuel Injection Pump Replacement

Important: If injection pump is faulty, the new injection pump must be timed. Refer to Checking/Adjust Injection Timing

Is the action complete?

--

Go to Step 18

--

17

Replace the faulty PCM.

Important: If the PCM is faulty, the new PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming

Is the action complete?

--

Go to Step 18

--

18

  1. Using the Scan Tool, select DTC, Clear Info.
  2. Start engine and idle at normal operating temperature.
  3. Select DTC, Specific, then enter the DTC number which was set.
  4. Operate vehicle within the conditions for setting this DTC as specified in the supporting text.

Does the Scan Tool indicate that this diagnostic Ran and Passed?

--

Go to Step 19

Go to Step 2

19

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