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DTC P0689, P068A, P068B, or P0690 — LNP or LNQ

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0689 00: Engine Controls Ignition Relay Feedback Circuit Low Voltage

DTC P068A 00: Engine Controls Ignition Relay De-Energised Too Early

DTC P068B 00: Engine Controls Ignition Relay De-Energised Too Late

DTC P0690 00: Engine Controls Ignition Relay Feedback Circuit High Voltage

Circuit/System Description

The powertrain relay, is controlled by the engine control module (ECM) depending upon input from the ignition switch. Battery positive voltage is supplied to the relay coil and switch. When the ignition switch is turned to the ON position, the ECM will provide ground on the control circuit of the powertrain relay using a low side driver. This will allow voltage through the relay switch contacts to the components. The ECM monitors the voltage level on the control circuit of the powertrain relay.

Conditions for Running the DTC

    • The ignition is ON or the engine is running.
    • The ignition voltage is between 11-18 V.
    • These DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0689 00

The ECM detects the engine controls powertrain relay feedback circuit is less than 5 V when the relay is commanded ON for 5 s.

P068A 00

The ECM detects the engine controls powertrain relay feedback is detecting the circuit is turning off before the ECM is commanding off for less than 5 s.

P068B 00

The ECM detects the engine controls powertrain relay feedback is detecting the circuit is staying on when commanded off for less than 5 s.

P0690 00

    • The ECM detects the engine controls powertrain relay feedback circuit is greater than 2 V when the relay is commanded OFF.
    • The ECM detects the engine controls powertrain relay feedback circuit is greater than 18 V when the relay is commanded ON.

Action Taken When the DTC Sets

DTCs P0689 00, P068A 00, P068B 00 and P0690 00 are Type B DTCs

Conditions for Clearing the DTC

DTCs P0689 00, P068A 00, P068B 00 and P0690 00 are Type B DTCs

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Cycle the ignition from OFF to ON. You should hear and feel an audible click from the KR75 Powertrain Relay. Repeat as necessary in order to verify KR75 Powertrain Relay operation.
  2. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Circuit/System Testing

  1. Ignition OFF, disconnect the KR75 Powertrain Relay.
  2. Ignition ON, verify a test lamp illuminates between the B+ circuit terminals 85 and 30 and ground.
  3. If the test lamp does not illuminate, test the B+ circuits for a short to ground or an open/high resistance. Replace the fuse if necessary.
  4. Ignition OFF, connect a test lamp between the control circuit terminal 86 and the B+ circuit terminal 85.
  5. If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
  6. Ignition ON. The test lamp should turn ON.
  7. If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
  8. Install a 20 A fused jumper wire between the B+ circuit terminal 87 and the ignition circuit terminal 30.
  9. Attempt to start the engine. The engine should start.
  10. If the engine does not start, test the ignition circuit between the KR75 Powertrain Relay and the K20 Engine Control Module for a short to ground or for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
  11. If all circuits test normal, test or replace the KR75 Powertrain Relay.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the KR75 Powertrain Relay.
  2. Measure for 70-110 Ω between terminals 85 and 86 of the KR75 Powertrain Relay.
  3. If the resistance is not within the specified range, replace the KR75 Powertrain Relay.
  4. Measure for infinite resistance between following terminals of the KR75 Powertrain Relay:
  5. • Terminals 30 and 86
    • Terminals 30 and 87
    • Terminals 30 and 85
    • Terminals 85 and 87
         ⇒If continuity is detected, replace the KR75 Powertrain Relay.
  6. Connect a 20 A fused jumper wire from the positive terminal of the battery to KR75 Powertrain Relay terminal 85. Connect a jumper wire from the negative terminal of the battery to KR75 Powertrain Relay terminal 86. Measure for less than 5 Ω between KR75 Powertrain Relay terminal 30 and KR75 Powertrain Relay socket terminal 87.
  7. If the resistance measures more than 5 Ω, replace the KR75 Powertrain Relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Relay Replacement : Within an Electrical Center → Attached to Wire Harness
    • Control Module References for ECM replacement, setup, and programming
   


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