For 1990-2009 cars

### 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 Descriptor

DTC C0870 03: Control Module Voltage Reference Output Circuit Low Voltage
DTC C0870 07: Control Module Voltage Reference Output Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
5 V Reference | C0870 03 | C0595 05, C0600 05, C0605 05, C0670 05, C0675 05 | C0870 07 | --
Low Reference | -- | C0595 05, C0600 05, C0605 05, C0670 05, C0675 05 | -- | --

### Circuit/System Description

The suspension control module supplies a 5 V reference voltage and a low reference to each body acceleration sensor and wheel acceleration sensor. The body acceleration sensors and wheel acceleration sensors supply a signal of 0.5-4.5 V to the suspension control module.

### Conditions for Running the DTC

System voltage is between 9 and 16 V

### Conditions for Setting the DTC

#### C0870 03

The 5 V reference voltage is less than 4.5 V for 1.5 s

#### C0870 07

The 5 V reference voltage is greater than 5.5 V for 1.5 s

### Action Taken When the DTC Sets

• | The electronic suspension control is disabled for the duration of the ignition cycle.

• | The driver information center displays the SERVICE SUSPENSION SYSTEM message

### Conditions for Clearing the DTC

• | A present DTC will clear on the next consecutive malfunction-free ignition cycle.

• | A history DTC will clear after 41 consecutive malfunction-free ignition cycles.

### Reference Information

#### Schematic Reference

Electronic Suspension Control Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Electronic Suspension Control Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

Ignition ON, observe the scan tool Suspension Position Sensor 5V Reference parameter. The reading should be 5 V.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connectors at all the body acceleration sensors and wheel acceleration sensors.
2. Ignition ON, test for 4.8-5.2 V between one of the 5 V reference circuits terminal 1 and ground.

⇒ | If less than the specified range, test the 5 V reference circuit for a short to ground. If the circuit tests normal, replace the K19 Electronic Suspension Control (ESC) Module.

⇒ | If greater than the specified value, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K19 Electronic Suspension Control (ESC) Module.

3. Ignition OFF, connect each component associated with the 5 V reference circuit one at a time while observing the scan tool Suspension Position Sensor 5V Reference parameter. Verify the reading is 5 V.

⇒ | If not the specified value when a component is connected, test the signal circuit terminal 2 of that component for a short to voltage. If the circuit tests normal, replace the component.

### Repair Instructions

• | Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Electronic Suspension Front Position Sensor Replacement

• | Electronic Suspension Rear Position Sensor Replacement

• | Control Module References for suspension control module replacement, setup and programming