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Home >> Cadillac >> 2012 >> Escalade EXT >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls/Fuel - 5.3L, 6.0L, 6.2L - DTC P0010 To DTC P0358 >> Diagnostic Information and Procedures >> DTC P0101 >> Circuit/System Testing

Circuit/System Testing

NOTE:

You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Verify the integrity of the entire air induction system by inspecting for the following conditions:
    • Improperly installed components
    • Collapsed, restricted, or damaged components
    • Loose clamps, cracks, or other damage
    • An air flow restriction
    • Restricted air filter
    • Splits, kinks, leaks, or improper connections at the vacuum hoses
    • Vacuum leaks at the intake manifold, MAP sensor, and throttle body
    • Water intrusion
    • In cold climates, inspect for any snow or ice buildup
    • Inspect the B75B mass air flow sensor element for contamination
    • If a condition is found 

      If a condition is found, repair or replace component as appropriate.

    • No condition found 
  2. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B75B mass air flow /intake air temperature sensor. It may take up to 2 minutes for all vehicle systems to power down.
  3. Test for less than 2 Ω between the ground circuit terminal B and ground.
    • If 2 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 2 Ω 
  4. Ignition ON, verify a test lamp illuminates between the ignition 1 voltage circuit terminal C and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ignition 1 voltage circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the ignition 1 voltage circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for greater than 2 Ω between the ignition 1 voltage circuit terminal C and ground.
      • If less than 2 Ω, repair the short to ground on the circuit.
      • If greater than 2 Ω, refer to DTC P0685, P0689, P0690, or P1682 to verify the operation of the Powertrain Ign 1 Relay.
    • If the test lamp illuminates 
  5. Ignition ON, test for 4.8-5.2 volts between the signal circuit terminal A and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the harness connector at the K20 ECM.
    2. 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
    3. 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 ECM.
    • If greater than 5.2 V 
    1. Ignition OFF, disconnect the harness connector at the K20 ECM, ignition ON.
    2. 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 ECM.
    • If between 4.8-5.2 V 
  6. Ignition OFF, connect the red lead of the J 38522  Variable Speed Generator to the signal circuit terminal A at the harness connector. Connect the battery voltage supply to B+, and the black lead to ground.
  7. Set the J 38522  Variable Speed Generator to the following specifications.
    • Signal switch to 5 V
    • Frequency switch to 5 KHz
    • Duty Cycle switch to Normal
  8. Engine idling, observe the scan tool MAF Sensor parameter. The scan tool MAF Sensor parameter should be between 4, 950-5, 050 Hz.
    • If not between 4, 950-5, 050 Hz. 

      If not between 4, 950-5, 050 Hz., replace the K20 ECM.

    • If between 4, 950-5, 050 Hz. 
  9. Test or replace the B75B mass air flow/intake air temperature sensor.
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