P1270
P1270-INTAKE MANIFOLD RUNNER (SWIRL) PERFORMANCE
For a complete wiring diagram Consult Diagrams/Electrical
- When Monitored:
With the ignition on and the Intake Swirl Servo Motor command on.
- Set Condition:
The Engine Control Module (ECM) detects that the (N117) Intake Swirl Servo Motor Control circuit voltage is implausible.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.
Diagnostic Test
1. DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, Clear DTCs in the Engine Control Module (ECM).
With the scan tool, actuate the Swirl Solenoid.
Monitor the scan tool for at least two minutes.
With the scan tool, select View DTCs.
Is the status Active for this DTC?
Yes
- Go To 3
No
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Component Tests and General Diagnostics
2. INTAKE SWIRL SERVO MOTOR
With the scan tool, actuate the Swirl Solenoid to 100%.
Using a 12 volt test light connected to 12 volts, check the (N117) Swirl Solenoid Control circuit in the Swirl Solenoid harness connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
NOTE: The circuit will remain actuated by the controller for 30 seconds. Be certain the actuation is active when checking the circuit.
With the scan tool, actuate the Swirl Solenoid to 0%.
Using a 12 volt test light connected to 12 volts, check the (N117) Swirl Solenoid Control circuit in the Swirl Solenoid harness connector.
NOTE: The test light should not be illuminated.
NOTE: The circuit will remain actuated by the controller for 30 seconds. Be certain the actuation is active when checking the circuit.
Is the test light illuminated and bright with the actuation at 100% and not illuminated with the actuation at 0%?
Yes
Go To 3
No
Go To 6
3. (N117) INTAKE SWIRL SERVO MOTOR CONTROL CIRCUIT SHORTED TO VOLTAGE
Turn the ignition off.
Disconnect the Intake Swirl Servo Motor harness connector.
Disconnect the Engine Control Module (ECM) harness connector.
Remove the ASD Relay.
Connect a jumper wire between cavity 4 (30) and cavity 1 (87) of the ASD Relay Connector.
Turn the ignition on.
Measure the voltage of the (N117) Intake Swirl Servo Motor Control circuit in the Intake Swirl Servo Motor harness connector.
Is there any voltage present?
Yes
- Repair the (N117) Intake Swirl Servo Motor Control circuit for a short to voltage.
- Perform the ECM Verification Test Ver. 1. Verification Tests
No
- Go to 4
4. (N117) INTAKE SWIRL SERVO MOTOR CONTROL CIRCUIT SHORTED TO GROUND
Turn the ignition off.
Remove the jumper wire and install the ASD Relay.
Measure the resistance between ground and the (N117) Intake Swirl Servo Motor Control circuit in the Intake Swirl Servo Motor harness connector.
Is the resistance above 10.0 ohms?
Yes
- Go to 5
No
- Repair the (N117) Intake Swirl Servo Motor Control circuit for a short to ground.
- Perform the ECM Verification Test Ver. 1. Verification Tests
5. (N117) INTAKE SWIRL SERVO MOTOR CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
Measure the resistance of the (N117) Intake Swirl Servo Motor Control circuit between the Intake Swirl Servo Motor harness connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?
Yes
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Swirl Solenoid and the Engine Control Module (ECM).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals.
- Search for any Technical Service Bulletins that may apply.
- If none of the above are found, replace the Engine Control Module (ECM).
- Perform the ECM Verification Test Ver. 1. Verification Tests
No
- Repair the (N117) Swirl Solenoid Control circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests
6. (A15) FUSED ASD RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE
Turn the ignition off.
Connect the Engine Control Module (ECM) harness connector.
Turn the ignition on.
Using a 12 volt test light connected to ground, check the (A15) Fused ASD Relay Output circuit in the Intake Swirl Servo Motor 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 (A15) Fused ASD Relay Output circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests
7. (Z42) GROUND CIRCUIT OPEN
Turn the ignition off.
Measure the resistance between the (Z42) Ground circuit and ground
Is the resistance below 5.0 ohms?
Yes
Go To 8
No
- Repair the open in the (Z24) Ground circuit.
- Perform the ECM Verification Test Ver. 1. Verification Tests
8. INTAKE MANIFOLD RUNNER (SWIRL) MOTOR/LINKAGE
Remove the Intake Manifold. Intake Manifold - Removal
Inspect the Intake Manifold and Intake Manifold Runner (Swirl) Assembly for:
- Coking around the butterfly valves.
- Loose or missing butterfly valves.
- Stuck butterfly valves.
- Missing linkage clips.
- Broken or binding linkage.
Is there any damage to the Intake Manifold Runner (Swirl) Motor, Linkage or Butterfly Valves.
Yes
- Replace the Intake Manifold.
NOTE: If the Intake Manifold Runner (Swirl) linkage was found to be binding, reconnect the (Swirl) Motor harness connector and actuate with the scan tool. If the Manifold Runner Motor does not actuate back and forth smoothly then replace Manifold Runner Motor with the Intake Manifold.
No
- Replace Intake Manifold Runner (Swirl) Motor.
- Perform the ECM Verification Test Ver. 1. Verification Tests