Diagnostic System Check

Install scan tool. If scan tool powers up, go to next step. If scan tool does not power up, see SCAN TOOL DOES NOT POWER UP in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
Turn ignition on, engine off. Try to establish scan tool communication with Driver Information Center (DIC), Electronic Brake Control Module (EBCM), Instrument Panel Cluster (IPC), Instrument Panel integration Module (IPM) and Powertrain Control Module (PCM). If communication with all modules is established, go to next step. If communication with any module is not established, see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
Select display DTC function for each module. Record all displayed DTCs, status of displayed DTCs and module that set DTC. If DTCs are displayed, go to next step. If no DTCs are displayed, see SYMPTOM DIAGNOSIS .
Retrieve codes and perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS table.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC

Description

BXXXX

⁽¹⁾

C1211

ABS Indicator Signal Circuit High

C1214

System Relay Contact Or Coil Circuit Open

C1217

BPMV Pump Motor Control Circuit Short

C1218

Pump Motor Voltage

C1221-C1224

Wheel Speed Sensor Input Signal Is Zero

C1225-C1228

Excessive Wheel Speed Variation

C1232-C1235

Wheel Speed Sensor Circuit Open Or Shorted

C1236

Low System Supply Voltage

C1237

High System Supply Voltage

C1238

Drive Wheel Brake Rotor Excessive Temperature

C1242

BPMV Pump Motor Short To Ground

C1243

BPMV Pump Motor Stalled

C1245

Tire Inflation Monitor

C1246

Brake Lining Wear Circuit Open

C1248

Dynamic Rear Proportioning Control System

C1251 ⁽²⁾

RSS Indicated Malfunction

C1252 ⁽³⁾

LF Normal Force Malfunction

C1253 ⁽³⁾

RF Normal Force Malfunction

C1254

Checksum Error

C1255

EBTCM Internal Malfunction (ABS/TCS Disabled)

C1256

EBTCM Internal Malfunction

C1261

LF Inlet Solenoid Valve Malfunction

C1262

LF Outlet Solenoid Valve Malfunction

C1263

RF Inlet Solenoid Valve Malfunction

C1264

RF Outlet Solenoid Valve Malfunction

C1265

LR Inlet Solenoid Valve Malfunction

C1266

LR Outlet Solenoid Valve Malfunction

C1267

RR Inlet Solenoid Valve Malfunction

C1268

RR Outlet Solenoid Valve Malfunction

C1271

LF TCS Master Cylinder Isolation Valve Malfunction

C1272

LF TCS Prime Valve Malfunction

C1273

RF TCS Master Cylinder Isolation Valve Malfunction

C1274

RF TCS Prime Valve Malfunction

C1276

Delivered Torque Signal Circuit Malfunction

C1277

Requested Torque Signal Circuit Malfunction

C1278

TCS Temporarily Inhibited By PCM

C1281

Steering Sensor Uncorrelated Malfunction

C1282

Yaw Rate Sensor Bias Circuit Malfunction

C1283

Excessive Time To Center Steering

C1284

Lateral Accelerometer Self Test Malfunction

C1285

Lateral Accelerometer Circuit Malfunction

C1286

Steering Sensor Bias Malfunction

C1287

Steering Sensor Rate Malfunction

C1288

Steering Sensor Circuit Malfunction

C1291

Open Brakelight Switch Contacts During Deceleration

C1293

DTC C1291 Set In Previous Ignition Cycle

C1294

Brakelight Switch Circuit Always Active

C1295

Brakelight Switch Circuit Open

C1298 ⁽⁴⁾

Class 2 Serial Data Link Malfunction

P1571

Requested Torque Signal Circuit Malfunction

P1644

Delivered Torque Signal Voltage Invalid

P1689

Delivered Torque Signal Voltage Invalid

PXXXX

⁽⁵⁾

UXXXX

⁽⁶⁾

⁽¹⁾	See DIAGNOSTIC TESTS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.

⁽²⁾	Cadillac only.

⁽³⁾	2000 Cadillac only.

⁽⁴⁾	2000 models only.

⁽⁵⁾	For any DTC beginning with the letter "P" except P1571, P1644 or P1689, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

⁽⁶⁾	For any DTC beginning with the letter "U", see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.