DTC P1682: Ignition 1 Switch Circuit 2
This document provides diagnostic instructions and procedures for DTC P1682 in the 2010 Chevrolet Equinox.
Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle before using this procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic approach.
- Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P1682: Ignition 1 Switch Circuit 2
Diagnostic Fault Information
| Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
|---|---|---|---|
| Engine Controls Ignition Relay Feedback Signal, Engine Control Module Relay | P1682 | P1682 | P0690 |
| Ignition 1 Signal, Ignition Main Relay | 1 | 1 | 2 |
1. A short to ground or open/high resistance will cause a No Crank condition.
2. A short to voltage will cause the engine to continue to run with ignition OFF.
Typical Scan Tool Data
| Circuit | Ignition 1 Signal | ||
|---|---|---|---|
| Short to Ground | Open | Short to Voltage | |
| Operating Conditions: Ignition ON, engine OFF, and ignition main and engine control module relays are commanded ON | |||
| Ignition 1 Signal, Ignition Main Relay | 0 V | 0 V | B+ |
| Engine Controls Ignition Relay Feedback Signal, Engine Control Module Relay | 0 V | 0 V | B+ |
Circuit/System Description
There are 2 ignition voltage circuits supplied to the engine control module (ECM). The first ignition circuit is provided by the engine controls ignition relay or the engine control module relay, through a fuse. This ignition voltage circuit supplies power to all the internal ECM circuits associated with the throttle actuator control (TAC) operation. The second ignition voltage circuit is supplied by the ignition main relay through a fuse, and is used to power the remaining internal ECM circuits. If the ECM detects a voltage difference between the 2 ignition voltage circuits, DTC P1682 will set.
Conditions for Running the DTC
- The ignition is ON.
- System voltage is more than 6 V.
- The engine control module relay is commanded ON.
- DTC P1682 runs continuously.
Conditions for Setting the DTC
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
DTC P1682 is a Type A DTC.
Conditions for Clearing the DTC
DTC P1682 is a Type A DTC.
Reference Information
Schematic Reference
- Engine Controls Schematics
- Power Distribution Schematics
Connector End View Reference
- Component Connector End Views
Electrical Information Reference
- Circuit Testing
- Connector Repairs
- Electrical Center Identification Views
- Probing Electrical Connectors
- 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
Note: On the scan tool, the engine control module relay is referred to as the engine controls ignition relay.
- Ignition ON, observe the DTC information with a scan tool. If DTCs P0685, P0689, or P0690 are set, diagnose those DTCs first. DTC P1682 should not set.
- Ignition ON, observe the scan tool Ignition 1 Voltage signal and the Engine Controls Ignition Relay Feedback Signal parameters. There should be no more than 3 V difference between the two parameters.
- 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
Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
- Ignition ON, observe the Ignition 1 Signal and the Engine Controls Ignition Relay Feedback Scan Tool parameters to determine which is more than 3 V lower than the other. Note: The ignition 1 signal is supplied by the ignition main relay. The engine controls ignition relay feedback signal is supplied by the engine control module relay.
- Ignition OFF, remove the relay that corresponds to the scan tool parameter that is more than 3 V lower. Note: A resistance of 6 Ω or greater in the circuit/underhood fuse block will cause the DTC to set.
- Connect a 20 A fused jumper wire between B+ and the applicable ignition voltage circuit terminal 30 leading to the K20 ECM. Ignition ON, verify that the applicable scan tool parameter displays between 9–14 V.
- If the applicable scan tool parameter is less than the specified value, test the ignition voltage circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.
- Ignition OFF, connect a DMM set to the diode setting between the control circuit terminal 85 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 ECM.
- 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 ECM.
- If all circuits test normal, replace the applicable relay.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Relay Replacement
- Control Module References for ECM replacement, setup, and programming
