P0690
DTC P0685, P0689, P0690, or P1682 (LUW)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P0685
- Engine Controls Ignition Relay Control Circuit
DTC P0689
- Engine Controls Ignition Relay Feedback Circuit Low Voltage
DTC P0690
- Engine Controls Ignition Relay Feedback Circuit High Voltage
DTC P1682
- Ignition 1 Switch Circuit 2
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The engine controls ignition or powertrain relay is an electrical switch that opens and closes under the control of the engine control module. The powertrain relay switch is held in the open position by spring tension. Battery positive voltage is supplied directly to the relay coil and the relay switch contact at all times. The engine control module (ECM) supplies the ground path to the relay coil control circuit through an output driver module. The output driver module for the ignition main relay also incorporates a fault detection circuit, which is continuously monitored by the ECM. When the ECM commands the powertrain relay ON, switched battery voltage is supplied to fuses in the underhood fuse block. The switched battery voltage that is supplied to the ECM, provides power to the internal ECM circuits associated with the throttle actuator control (TAC) operation. The ECM also monitors the voltage level on the switched battery circuit to confirm that the powertrain relay contacts have closed.
Conditions for Running the DTC
P0685
* The ignition is ON, or the engine is running.
* The ignition voltage is between 11-32 V.
* The DTC runs continuously once the above conditions are met.
P0689
* DTC P0685 is not set.
* Powertrain relay is commanded ON.
* The run/crank voltage is greater than 11 V.
* The DTC runs continuously once the above conditions are met.
P0690
* DTC P0685 is not set.
* Powertrain relay is commanded ON.
* The ignition is ON.
* The DTC runs continuously when the above conditions are met.
P1682
* The engine controls ignition relay is commanded ON.
* The run/crank voltage is greater than 5.5 V
* The DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
P0685
The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 2 s.
P0689
The ECM detects that the engine controls powertrain relay feedback circuit is less than 5 V when the relay is commanded ON for 5 s.
P0690
The ECM detects the engine controls powertrain relay feedback circuit is greater than 4 V when the relay is commanded OFF for greater than 2 s.
P1682
The ECM detects that the voltage level difference is greater than 3 V between the 2 ignition voltage circuits for less than 1 s.
Action Taken When the DTC Sets
* DTCs P0685 and P0690 are Type B DTCs.
* DTC P0689 is a Type C DTC.
* DTC P1682 is a Type A DTC.
Conditions for Clearing the DTC
* DTCs P0685 and P0690 are Type B DTCs.
* DTC P0689 is a Type C DTC.
* DTC P1682 is a Type A DTC.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
Note:
* A short to voltage on other components may cause DTC P0690 to set. If other DTCs are set, diagnose those DTCs first.
* If you were sent here from engine cranks but does not run proceed to circuit/system testing.
1. Ignition ON, command the Engine Controls (EC) Ignition Relay ON and OFF with a scan tool while observing the parameters listed below. The parameters should not display Malfunction.
* Engine Controls Ignition Relay Control Circuit Low Voltage Test Status
* Engine Controls Ignition Relay Control Circuit Open Test Status
* Engine Controls Ignition Relay Control Circuit High Voltage Test Status
2. Ignition ON, observe the DTC information with a scan tool. DTC P0685, P0689, P0690, or P1682 should not set.
3. Observe the scan tool Ignition 1 Voltage Signal and the Engine Controls Ignition Relay Feedback Signal parameters. There should be less than 3 V difference between the two parameters.
4. 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 observed from the freeze frame/failure records data.
Circuit/System Testing
Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing unless sent here from Engine Cranks But Does Not Run.
1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.
2. Verify that a test lamp illuminates between ground and the relay circuit terminals listed below:
* Terminal 85
* Terminal 30
• If the test lamp does not illuminate, test the relay battery voltage circuit for an/high resistance.
Note: High resistance in the circuit/underhood fuse block either the engine controls ignition relay or the ignition main relay can cause DTC P1682 to set.
3. Ignition ON, verify that a test lamp does not illuminate between the ignition voltage circuit terminal 87 and ground.
• If the test lamp illuminates, test the ignition voltage circuit for a short to voltage.
4. Connect a 20 A fused jumper wire between the relay switch B+ circuit terminal 30 and the relay switch ignition voltage circuit terminal 87.
5. Ignition ON, observe the scan tool Engine Controls Ignition Relay Feedback Signal parameter. The ECM should communicate, and the parameter should display B+.
• If not the specified value, or the ECM does not communicate, test the ignition voltage circuit between the engine controls ignition relay and the ECM for a short to ground or for an open/high resistance. If the circuit/connections test normal, replace the K20 Engine Control Module.
6. Ignition OFF, connect a DMM set to the diode setting between control circuit terminal 86 and ground. Verify the DMM displays OL.
• If not the specified value, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.
7. Ignition ON, verify the DMM displays less than 1 V.
• If not the specified range, 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. If all circuits test normal, replace the KR75 Engine Controls Ignition Relay.
Component Testing
Relay Test
1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.
2. Measure for 70-110 ohms between terminals 1 and 2 of the KR75 Engine Controls Ignition Relay.
• If the resistance is not within the specified range, replace the KR75 Engine Controls Ignition Relay.
3. Measure for infinite resistance between following terminals of the KR75 Engine Controls Ignition Relay:
* Terminals 3 and 1
* Terminals 3 and 5
* Terminals 3 and 2
* Terminals 2 and 5
• If continuity is detected, replace the KR75 Engine Controls Ignition Relay.
4. Connect a 20 A fused jumper wire from the positive terminal of the battery to KR75 Engine Controls Ignition Relay terminal 2. Connect a jumper wire from the negative terminal of the battery to KR75 Engine Controls Ignition Relay 1. Measure for less than 5 ohms between KR75 Engine Controls Ignition Relay 3 and KR75 Engine Controls Ignition Relay socket terminal 5.
• If the resistance measures more than 5 ohms, replace the KR75 Engine Controls Ignition Relay.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Relay Replacement (Within an Electrical Center) Relay Replacement (Within an Electrical Center)Relay Replacement (Attached to Wire Harness) Relay Replacement (Attached to Wire Harness)
* Control Module References Control Module References for Engine Control Module replacement, programming and setup.