P0206

P0206-FUEL INJECTOR 6 CIRCUIT/OPEN





For a complete wiring diagram Consult Diagrams/Electrical

Theory of Operation

The fueling strategy for NGC requires potentially three fuel pulses per cylinder per cycle. The first pulse is delivered starting at a programmed angle soon after the intake valve closes, for specified time duration. This is for two reasons, one to prevent any fuel from this pulse being delivered in the previous cycle and second to allow fueling to begin as early as possible in the current cycle. The second pulse is delivered for a specified time and is set to end at a programmed angle. The pulse must not extend past the end angle. There can be a separate value for each cylinder under the same operating conditions. This is done for two reasons, one to prevent any fuel from this pulse being delivered during the intake/exhaust valve overlap period, which tends to cause elevated emission levels. Also, allowing fuel to enter each cylinder at a slightly different angle tends to reduce any fuel pressure standing waves in the fuel rail. If the desired total fuel pulse-width increases, a third fuel pulse must be delivered. The third pulse, if necessary, is delivered for a specified time and must end at a programmed angle before the valve closes again. The third pulse in the cycle is controlled by its ending angle. This is also for two reasons, one to prevent any fuel from this pulse being delivered in the next cycle and second to allow fueling to end as late as possible in the current cycle. At high engine speeds, one or more of the pulses may be dropped from the fueling strategy.

- When Monitored:
With the engine running, battery voltage greater than 12 volts, and engine RPM less than 3000.

- Set Condition:
The PCM monitors the continuity of the injector circuits as well as the voltage spike created by the collapse of the magnetic field in the injector coil. Any condition that reduces the maximum current flow or the magnitude of the voltage spike can cause this DTC to set.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE
Turn the ignition on.
With the scan tool, select View DTCs. Record DTC and Freeze Frame information.
Start the engine and allow it to reach operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

NOTE: Review Freeze Frame information. Operate the vehicle under conditions similar to which the DTC was set.

With a scan tool, select View DTCs.
Is the DTC Active at this time?

Yes

- Go to 2

No

- Refer to the CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking For An Intermittent DTC

2. (K58) INJECTOR 6 CONTROL CIRCUIT SHORTED TO VOLTAGE




Turn the ignition off.
Remove the ASD Relay.
Disconnect the C2 Powertrain Control Module (PCM) connector.
Turn the ignition on.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the voltage of the (K58) Injector 6 Control circuit at the appropriate terminal of special tool #8815.
Is there any voltage present?

Yes

- Repair the short to voltage in the (K58) Injector 6 Control circuit.
- Perform the PCM Verification Test. Powertrain Verification Test

No

- Go to 3

3. (K58) INJECTOR 6 CONTROL CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Measure the resistance between ground and the (K58) Injector 6 Control circuit at the appropriate terminal of special tool #8815.
Is the resistance above 100 ohms?

Yes

- Go to 4

No

- Repair the short to ground in the (K58) Injector 6 Control circuit.
- Perform the PCM Verification Test. Powertrain Verification Test

4. FUEL INJECTOR 6 CIRCUIT RESISTANCE




Turn the ignition off.
Measure the resistance of the Fuel Injector 6 circuit between the ASD Relay connector and the appropriate terminal of special tool #8815.

NOTE: The resistance of the circuit will vary according to the temperature of the injector coil. Use the table below to determine the resistance range of the injector.





Is the resistance of the injector within the specified range?

Yes

- Go to 9

No

- Go to 5

5. FUEL INJECTOR 6 WIRING AND CONNECTOR INSPECTION
Turn the ignition off.
Verify that the connector is properly connected to the injector.
Disconnect the Fuel Injector 6 connector and inspect the wiring and terminals for any condition that would result in a poor connection.
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Verify that there is good pin to terminal contact in the Injector and Powertrain Control Module connectors.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. Powertrain Verification Test

No

- Go to 6

6. (F343) FUSED ASD RELAY OUTPUT




Turn the ignition off.
Connect the C2 Powertrain Control Module (PCM) connector.
Install the ASD Relay.
Turn the ignition on.
With the scan tool, actuate the Auto Shutdown (ASD) Relay Control State.
Using a 12 volt test light connected to ground, check the (F343) Fused ASD Relay Output circuit in the Fuel Injector 6 harness connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go to 7

No

- Repair the short to ground or excessive resistance in the (F343) Fused ASD Relay Output circuit.
- Perform the PCM Verification Test. Powertrain Verification Test

7. (K58) INJECTOR 6 CONTROL CIRCUIT OPEN OR HIGH RESISTANCE




Turn the ignition off.
Disconnect the C2 Powertrain Control Module (PCM) connector.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (K58) Injector 6 Control circuit between the Fuel Injector 6 harness connector and the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

Yes

- Go to 8

No

- Repair the (K58) Injector 6 Control circuit for an open circuit or high resistance.
- Perform the PCM Verification Test. Powertrain Verification Test

8. FUEL INJECTOR 6
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Injector 6 and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Verify that there is good pin to terminal contact in the Injector and Powertrain Control Module connectors.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. Powertrain Verification Test

No

- Replace the Fuel Injector 6.
- Perform the PCM Verification Test. Powertrain Verification Test

9. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Injector 6 and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Verify that there is good pin to terminal contact in the Injector and Powertrain Control Module connectors.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test. Powertrain Verification Test