For a complete wiring diagram Refer to Section 8W.When Monitored:Ignition on and engine running with no MAP Sensor DTCs.Set Condition:A large vacuum leak has been detected or both of the TP Sensors have failed based on their position being 2.5 volts and the calculated MAP value is less than the actual MAP minus an Offset value. One trip fault and the code will set within 5 seconds. ETC light will flash.Possible CausesVACUUM LEAKRESISTANCE IN THE (F856) 5-VOLT SUPPLY CIRCUIT(F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUNDRESISTANCE IN THE (K1) MAP SIGNAL CIRCUIT(K1) MAP SIGNAL CIRCUIT SHORTED TO GROUNDRESISTANCE IN THE (K900) SENSOR GROUND CIRCUITRESISTANCE IN THE (F855) 5-VOLT SUPPLY CIRCUIT(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUNDRESISTANCE IN THE TP SENSOR SIGNAL CIRCUITTP SENSOR SIGNAL CIRCUIT SHORTED TO GROUNDRESISTANCE IN THE (K922) TP RETURN CIRCUITMAP SENSORTP SENSORPCMAlways perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).1. ACTIVE DTCThe most likely cause of this DTC is a vacuum leak.Diagnose any 5-Volt Supply, TP Sensor, Fuel System Lean or Rich, or MAP Sensor DTCs before continuing.The throttle plate should be free from binding and carbon build up.Ignition on, engine not running.With a scan tool, select View DTCs.Is the DTC Active at this time?YesGo To 2NoRefer to the INTERMITTENT CONDITION Diagnostic Procedure.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)2. VACUUM LEAKThis code is enabled on engines with a plastic intake manifold and is intended to limit the maximum engine speed if a large crack occurs.A large vacuum leak is most likely the cause of this DTC.Inspect the Intake Manifold and Throttle body for leaks and cracks.Inspect the Power Brake Booster for any vacuum leaks.Inspect the PCV system for proper operation or any vacuum leaks.Inspect the MAP Sensor for proper installation.Were any vacuum leaks found?YesRepair the vacuum leak as necessary.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 33. MAP SENSOR OPERATIONStart the engine.With a scan tool, monitor the MAP Sensor voltage.Snap the Accelerator pedal.Does the MAP Sensor voltage vary from below 2.0 volts at idle to above 3.5 volts at Wide Open Throttle?YesGo To 4NoGo To 134. TP SENSOR OPERATIONIgnition on, engine not running.With a scan tool, perform the Throttle Follower Test.TP Sensor No.1 should start at approximately 0.8 of a volt and increase to 4.2 volts.TP Sensor No.2 should start at approximately 4.2 volts and decrease to 0.8 of a volt.Is the voltage transition smooth between the appropriate values?YesRefer to the INTERMITTENT CONDITION Diagnostic Procedure.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 55. RESISTANCE IN THE (F855) 5-VOLT SUPPLY CIRCUIT

Turn the ignition off.Disconnect the Throttle Body harness connector.Disconnect the C2 PCM harness connector.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 (F855) 5-volt Supply circuit from the Throttle Body harness connector to the appropriate terminal of special tool #8815.Is the resistance above 100 ohms?YesGo To 6NoRepair the excessive resistance in the (F855) 5-volt Supply circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)6. (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and (F855) 5-volt Supply circuit at the Throttle Body harness connector.Is the resistance above 100 ohms?YesGo To 7NoRepair the short to ground in the (F855) 5-volt Supply circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)7. TP SENSOR

Connect the C2 PCM harness connector.Ignition on, engine not running.With a scan tool, monitor the TP Sensor voltage.Connect a jumper wire between the (K22) TP Signal 1 circuit and the (K922) TP Return circuit in the Throttle Body harness connector.TP Sensor No.1 voltage should start at approximately 4.8 volts and decrease to 0.2 of a volt.Connect a jumper wire between the (K122) TP Signal 2 circuit and the (F855) 5-volt Supply circuit in the Throttle Body harness connector.TP Sensor No.2 voltage should start at approximately 0 volts and increase to 4.8 to 5.2 volts.Does the TP Sensor voltage change to the appropriate voltage with the jumper wire installed?YesDisconnect the Battery before replacing the Throttle Body Assembly. Replace the Throttle Body Assembly. After installation is complete, use a scan tool and select the ETC RELEARN functionPerform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 88. RESISTANCE IN THE (K22) TP SIGNAL 1 CIRCUIT

Turn the ignition off.Disconnect the C2 PCM harness connector.Measure the resistance of the (K22) TP Signal 1 circuit from the Throttle Body harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 9NoRepair the excessive resistance in the (K22) TP Signal 1 circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)9. RESISTANCE IN THE (K122) TP SIGNAL 2 CIRCUIT

Measure the resistance of the (K122) TP Signal 2 circuit from the Throttle Body harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 10NoRepair the excessive resistance in the (K122) TP Signal 2 circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)10. (K22) TP SIGNAL 1 CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K22) TP Signal 1 circuit at the Throttle Body harness connector.Is the resistance above 100 ohms?YesGo To 11NoRepair the short to ground in the (K22) TP Signal 1 circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)11. (K122) TP SIGNAL 2 CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K122) TP Signal 2 circuit at the Throttle Body harness connector.Is the resistance above 100 ohms?YesGo To 12NoRepair the short to ground in the (K122) TP Signal 2 circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)12. RESISTANCE IN THE (K922) TP RETURN CIRCUIT

Measure the resistance of the (K922) TP Return circuit from the Throttle Body harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 19NoRepair the excessive resistance in the (K922) TP Return circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)13. RESISTANCE IN THE (F856) 5-VOLT SUPPLY CIRCUIT

Turn the ignition off.Disconnect the MAP Sensor harness connector.Disconnect the C1 PCM harness connector.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 (F856) 5-volt Supply circuit from the MAP Sensor harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 14NoRepair the excessive resistance in the (F856) 5-volt Supply circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE) 14. (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (F856) 5-volt Supply circuit in the MAP Sensor harness connector.Is the resistance above 100k ohms?YesGo To 15NoRepair the short to ground in the (F856) 5-volt Supply circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)15. MAP SENSOR

Connect the C1 PCM harness connector.Ignition on, engine not running.With a scan tool, monitor the MAP Sensor voltage.Connect a jumper wire between the (K1) MAP Signal circuit and the (K900) Sensor ground circuit in the MAP Sensor harness connector.Cycle the ignition switch from off to on.With a scan tool, monitor the MAP Sensor voltage.Does the scan tool display MAP voltage from approximately 4.9 volts to below 0.5 volt with the jumper wire installed?YesReplace the MAP Sensor.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 16Remove the jumper wire before continuing.16. RESISTANCE IN THE (K1) MAP SIGNAL CIRCUIT

Turn the ignition off.Disconnect the C2 PCM harness connector.Measure the resistance of the (K1) MAP Signal circuit from the MAP Sensor harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 17NoRepair the excessive resistance in the (K1) MAP Signal circuitPerform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)17. (K1) MAP SIGNAL CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K1) MAP Signal circuit in the MAP Sensor harness connector.Is the resistance above 100k ohms?YesGo To 18NoRepair the short to ground in the (K1) MAP Signal circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)18. RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT

Measure the resistance of the (K900) Sensor ground circuit from the MAP Sensor harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 19NoRepair the excessive resistance in the (K900) Sensor ground circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)19. PCMBefore continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.Were there any problems found?YesRepair as necessary.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoReplace and program the Powertrain Control Module per Service Information.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)