Circuit/System Testing
WARNING: This page is about a different variant/trim than selected.
NOTE:
You must perform Circuit/System Verification before proceeding with Circuit/System Testing.
- Verify none of the following conditions exist:
- A loose or disconnected charge air cooler hose or pipe
- A blocked or obstructed charge air cooler, including: after-market grill covers
- Improper active grille air shudder operation.
- Any mud or dirt build-up at the charge air cooler
- A restricted or collapsed air intake duct
- An intake system leaks. Refer to Charge Air Cooler Diagnosis (Induction System Air Leak Test) , Charge Air Cooler Diagnosis (Induction System Smoke Test) and Charge Air Cooler Diagnosis for Induction System Smoke Testing.
- A MAP sensor seal that is leaking, missing or damaged
- A restricted or collapsed air intake duct
- A misaligned or damaged air intake duct
- Any water intrusion in the induction system
- An Intake Manifold Resonator with a leaking seal or a cracked or broken housing
- If a condition exists
Repair or replace the component as appropriate.
- If no condition exists
- Engine idling at operating temperature.
- Command the EGR solenoid to 0 % with a scan tool.
- Observe the Induction System Leak Indication parameter for 10 s. Verify the parameter stabilizes after 10 s and is between 0.80:1 and 1.20:1.
- Slowly increase the engine speed until reaching WOT.
- Verify the Induction System Leak Indication parameter stabilizes after 10 s and is between 0.80:1 and 1.20:1.
- If not stable after 10 s and between 0.80:1 and 1.20:1.
Test the charge air cooler system and air inlet system for leaks.
- If stable after 10 s and between 0.80:1 and 1.20:1.
- Ignition OFF and all vehicle systems OFF, disconnect the B75C Multifunction Intake Air Sensor. It may take up to 2 minutes for all vehicle systems to power down.
- Test for less than 2 Ω between the low reference circuit terminal 7 and ground.
- If 2 Ω or greater
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for less than 2 Ω in the low reference circuit end to end.
- If 2 Ω or greater, repair the open or high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If less than 2 Ω
- Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 8 and ground.
- If less than 4.8 V
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the signal circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If greater than 5.2 V
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.
- Ignition ON, test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K20 Engine Control Module.
- If between 4.8-5.2 V
- Ignition ON, verify the scan tool IAT Sensor 1 parameter is colder than -39°C (-38°F).
- If warmer than -39°C (-38°F).
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the signal circuit terminal 8 and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If colder than -39°C (-38°F).
- Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 8 and the low reference circuit terminal 7.
- Verify the scan tool IAT Sensor 1 parameter is warmer than 148°C (298°F).
- If colder than 148°C (298°F).
- Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
- Test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V
- Ignition OFF.
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If warmer than 148°C (298°F).
- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B193A Charge Air Cooler Inlet Temperature sensor. It may take up to 2 minutes for all vehicle systems to power down.
- Test for less than 2 Ω between the low reference circuit terminal 2 and ground.
- If 2 Ω or greater
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for less than 2 Ω in the low reference circuit end to end.
- If 2 Ω or greater, repair the open or high resistance in the circuit.
- If less than 2 Ω replace the K20 Engine Control Module.
- If less than 2 Ω
- Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 1 and ground.
- If less than 4.8 V
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the signal circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If greater than 5.2 V
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.
- Ignition ON, test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K20 Engine Control Module.
- If between 4.8-5.2 V
- Ignition ON, verify the scan tool IAT Sensor 3 parameter is colder than -39°C (-38°F).
- If warmer than -39°C (-38°F).
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the signal circuit terminal 1 and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If colder than -39°C (-38°F).
- Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2.
- Verify the scan tool IAT Sensor 3 parameter is warmer than 213°C (415°F).
- If colder than 213°C (415°F).
- Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
- Test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V
- Ignition OFF.
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If warmer than 213°C (415°F).
- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B193B Charge Air Cooler Outlet Temperature sensor. It may take up to 2 minutes for all vehicle systems to power down.
- Test for less than 2 Ω between the sensor low reference circuit terminal 2 and ground.
- If 2 Ω or greater
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for less than 2 Ω in the low reference circuit end to end.
- If 2 Ω or greater, repair the open or high resistance in the circuit.
- If less than 2 Ω replace the K20 Engine Control Module.
- If less than 2 Ω
- Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 1 and ground.
- If less than 4.8 V
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the signal circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If greater than 5.2 V
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.
- Ignition ON, test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K20 Engine Control Module.
- If between 4.8-5.2 V
- Ignition ON, verify the scan tool Charge Air Cooler Temperature parameter is colder than -39°C (-38°F).
- If warmer than -39°C (-38°F).
- Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
- Test for infinite resistance between the signal circuit terminal 1 and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- If colder than -39°C (-38°F).
- Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2.
- Verify the scan tool Charge Air Cooler Temperature parameter is warmer than 213°C (415°F).
- If colder than 213°C (415°F).
- Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
- Test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V
- Ignition OFF.
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K20 Engine Control Module.
- Test or replace the appropriate temperature sensor.