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PCM Harness Resistance

Turn ignition switch to LOCK position. Disconnect PCM and appropriate component harness connectors. Check for open or short circuits between PCM harness connector terminal and component harness connector terminal. See POWERTRAIN CONTROL MODULE (PCM) CONNECTOR I.D.  table. See WIRING DIAGRAMS - 3.1L article. If harness is open or shorted, repair as necessary.

Fig 1: Identifying Powertrain Control Module (PCM) Harness Connector Terminals
G98F00864Courtesy of GENERAL MOTORS CORP.
POWERTRAIN CONTROL MODULE (PCM) CONNECTOR I.D. (1)

Connector Terminal Wire Color Function
C1 1 & 2 ***** Not Used
C1 3 BLK/WHT Fuel Gauge Control
C1 4 LT GRN 1-2 Shift Solenoid Control
C1 5 DK BLU Cooling Fan High Speed Control
C1 6 DK GRN Cooling Fan Low Speed Control
C1 7 BLK Camshaft Position Sensor Signal
C1 8 PPL/WHT Crankshaft Position 3x Sensor Reference Signal
C1 9 LT BLU/BLK Crankshaft Position 24x Sensor Signal
C1 10-12 ***** Not Used
C1 14 ***** Not Used
C1 15 TAN Serial Data (UART)
C1 16 BLK/WHT Powertrain Control Module Ground
C1 17 BLK Intake Air Temperature Sensor Ground
C1 18 ***** Not Used
C1 19 PPL Powertrain Control Module Ignition Voltage
C1 20 ORG Powertrain Control Module Battery Voltage
C1 21-27 ***** Not Used
C1 28 TAN/WHT Heated Oxygen Sensor No. 2 Signal Low
C1 29 TAN Heated Oxygen Sensor No. 1 Signal Low
C1 30 PPL Torque Converter Clutch Brake Switch
C1 32 GRY/BLK EGR Control Ground
C1 33 DK BLU Bank No. 1 Knock Sensor Signal
C1 34-35 ***** Not Used
C1 36 BRN Charge Indicator Light Control
C1 37 ***** Not Used
C1 38 LT GRN/WHT Idle Air Control Valve B High
C1 39-42 ***** Not Used
C1 43 BLK Fuel Injector No. 1 Control
C1 44 YEL/BLK 2-3 Shift Solenoid Control
C1 45 ***** Not Used
C1 46 PNK/BLK Fuel Injector No. 3 Control
C1 47 LT GRN/BLK Fuel Injector No. 2 Control
C1 48 RED/BLK Crankshaft Position 3x Sensor Reference Low
C1 49-52 ***** Not Used
C1 53 TAN/BLK Bypass Valve Control
C1 54 WHT Ignition Control
C1 55 DK GRN/WHT Vehicle Speed Sensor Signal Output
C1 56 BLK/WHT Powertrain Control Module Ground
C1 57 BLK/WHT Powertrain Control Module Ground
C1 59 PPL Serial Data Class II)
C1 62 & 63 ***** Not Used
C1 64 YEL Vehicle Speed Sensor High
C1 65 PPL Vehicle Speed Sensor Low
C1 66 & 67 ***** Not Used
C1 68 YEL Transmission Range B Signal
C1 69 YEL Mass Air Flow Sensor Signal
C1 70 BK BLU Theft Deterrent Fuel Enable Signal
C1 71 ***** Not Used
C1 72 DK GRN Cruise Control Disable Signal
C1 73 BLK/WHT Fuel Injector No. 5 Control
C1 74 & 75 ***** Not Used
C1 76 DK GRN/WHT EVAP Canister Purge Valve Control
C1 77 & 78 ***** Not Used
C1 79 YEL/BLK Fuel Injector No. 6 Control
C1 80 ***** Not Used
C2 1 ***** Not Used
C2 2 WHT EVAP Canister Vent Valve Control
C2 3 DK GRN/WHT Fuel Pump Relay Control
C2 4 RED EGR Valve Control
C2 5 BRN/WHT Malfunction Indicator Light Control
C2 6 BRN/WHT Oil Level Indicator Control
C2 7 LT BLU/WHT Idle Air Control Valve A High
C2 8 & 9 ***** Not Used
C2 10 PPL Heated Oxygen Sensor No. 1 Signal
C2 11 PPL/WHT Heated Oxygen Sensor No. 2 Signal
C2 12-15 ***** Not Used
C2 16 WHT Transmission Range Switch A Signal
C2 17 RED Transmission Range Switch C Signal
C2 20 & 21 ***** Not Used
C2 22 LT GRN A/C Request Signal
C2 25 LT GRN Manifold Absolute Pressure Sensor Signal
C2 26 YEL Engine Coolant Temperature Sensor Signal
C2 27 RED/BLK A/C Pressure Sensor Signal
C2 28 BRN EGR Pintle Position Signal
C2 29 GRY Generator Terminal F" Signal
C2 30-32 ***** Not Used
C2 33 GRY Throttle Position Sensor Reference Voltage
C2 34 GRY A/C Pressure Sensor Reference Voltage
C2 35 BLK Fuel Tank Pressure Sensor Ground
C2 36 GRY Oil Change Soon Indicator Control
C2 37 & 38 ***** Not Used
C2 39 DK GRN/WHT A/C Clutch Relay Control
C2 40 & 41 ***** Not Used
C2 42 LT BLU/BLK Fuel Injector No. 4 Control
C2 43 ***** Not Used
C2 44 LT BLU/BLK Idle Air Control Valve A Low
C2 45-48 ***** Not Used
C2 49 LT GRN/BLK Idle Air Control Valve A High
C2 50 TAN Intake Air Temperature Sensor
C2 51-54 ***** Not Used
C2 55 DK GRN Fuel Tank Pressure Sensor Signal
C2 56 GRY Transmission Range Sensor C
C2 57 ***** Not Used
C2 58 BRN Engine Oil Level Sensor Signal
C2 59 WHT Cruise Control Status
C2 60 ***** Not Used
C2 61 RED Generator Terminal L Control
C2 62-65 ***** Not Used
C2 66 DK BLU Throttle Position Sensor Signal
C2 67 ***** Not Used
C2 68 YEL Transmission Fluid Temperature Sensor
C2 69 PPL Fuel Level Sensor Signal
C2 70 & 71 ***** Not Used
C2 72 RED/WHT Camshaft Position Sensor Ignition Voltage
C2 73 BLK Camshaft Position Sensor Ground
C2 74 & 75 ***** Not Used
C2 77 ***** Not Used
C2 78 BRN Torque Converter Clutch PWM Solenoid Control
C2 79 YEL Torque Converter Clutch Solenoid
C2 80 ***** Not Used
(1) See Fig 1 .
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