2001 GMC C3500 HD 8.1 G, AutomaticFACTORY OEM SERVICE PROCEDURE

Powertrain Control Module Connector End Views

Powertrain Control Module (PCM) - C1 (Blue)

GM655733
Connector Part Information
  • 12191489
  • 80-Way F Micro-Pack 100W Sealed (NAT)
Pin Wire Color Circuit No. Function
1 BLK/WHT 451 Ground
2 LT GRN 1867 12 Volt Reference
3 PNK/BLK 1746 Fuel Injector 3 Control
4 LT GRN/BLK 1745 Fuel Injector 2 Control
5 10 - - Not Used
11 LT BLU 1876 Knock Sensor 2 Signal
12 DK BLU/WHT 1869 CKP Sensor Signal
13 ORN/BLK 463 Requested Torque Signal
14 ORN/BLK 1061 UART Serial Data [Secondary]
15 DK BLU/WHT 774 UART Serial Data [Tertiary]
16 - - Not Used
17 DK BLU 1225 Transmission Fluid Pressure Switch Signal B
18 RED 1226 Transmission Fluid Pressure Switch Signal C
19 PNK 439 Ignition 1 Voltage
20 ORN 440 Battery Positive Voltage
21 YEL/BLK 1868 Low Reference
22 GRN LT 488 Power Take Off Switch - Enable
23 BLK 470 Low Reference
24 - - Not Used
25 TAN 413 HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)
26 TAN 413 HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)
27 - - Not Used
28 TAN 413 HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)
29 TAN 413 HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)
30 LT GRN 1478 Coolant Level Switch Signal
31 32 - - Not Used
33 PPL 420 TCC Brake Switch Signal
34 WHT 776 Transmission Range Switch Signal P
35 GRY 48 CPP Switch Signal
36 BLK 1744 Fuel Injector 1 Control
37 YEL/BLK 846 Fuel Injector 6 Control
38 PNK/WHT 1101 Damping Lift/Dive Signal
39 - - Not Used
40 BLK/WHT 451 Ground
41 PPL 719 Low Reference
42 - - Not Used
43 RED/BLK 877 Fuel Injector 7 Control
44 LT BLU/BLK 844 Fuel Injector 4 Control
45 GRY 474 5 Volt Reference
46 GRY 474 5 Volt Reference
47 GRY 596 5 Volt Reference
48 GRY 597 5 Volt Reference
49 50 - - Not Used
51 DK BLU 496 KS [1] Signal
52 YEL 2522 Power Take Off (PTO) Status
53 BLK 470 Low Reference (Allison)
53 BLK 407 Low Reference (4L80E)
54 ORN/BLK 469 Low Reference
55 BRN 1456 EGR Valve Position Signal
56 - - Not Used
57 ORN 440 Battery Positive Voltage
58 DK GRN 1049 ECM/PCM Class 2 Serial Data
59 YEL 710 Class 2 Serial Data
60 ORN/BLK 510 Low Reference
61 PNK/BLK 632 Low Reference
62 - - Not Used
63 GRY 720 Low Reference
63 TAN 413 HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)
64 - - Not Used
65 PPL 1670 HO2S High Signal [- Bank 2 Sensor 2]
66 PPL 1666 HO2S High Signal [- Bank 2 Sensor 1]
67 - - Not Used
68 PPL/WHT 1668 HO2S High Signal [- Bank 1 Sensor 2]
69 PPL/WHT 1665 HO2S High Signal [- Bank 1 Sensor 1]
70 BRN 1174 Oil Level Switch Signal
71 LT BLU 494 Power Take Off (PTO) Engine Defeat Switch
72 YEL 772 Transmission Range Switch Signal B
73 BRN/WHT 633 CMP Sensor Signal
74 YEL 410 ECT Sensor Signal
75 PNK 1020 Off/Run/Crank Voltage
76 BLK/WHT 845 Fuel Injector 5 Control
77 DK BLU/WHT 878 Fuel Injector 8 Control
78 PPL 2562 Power Take Off (PTO) Engage Signal
79 - - Not Used
80 ORN/BLK 510 Low Reference
Powertrain Control Module (PCM) - C2 (RED)

GM684875
Connector Part Information
  • 12191488
  • 80-Way F Micro-Pack 100W Sealed (NAT)
Pin Wire Color Circuit No. Function
1 BLK/WHT 451 Ground
2 WHT 2467 Unmanaged Torque Signal (M74)
2 BRN 418 TCC PWM Solenoid Valve Control (4L80E)
3 TAN 1465 Fuel Pump Relay Control [- Secondary]
4 - - Not Used
5 TAN/BLK 464 Delivered Torque Signal
6 RED/BLK 1228 PC Solenoid Valve High Control (Sol. A)
7 RED 1676 EGR Valve Supply Voltage
8 LT BLU/WHT 1229 PC Solenoid Valve Low Control (Sol. A)
9 DK GRN/WHT 465 Fuel Pump Relay Control [- Primary]
10 WHT 121 Engine Speed Signal
11 DK BLU 604 A/C High Pressure Recirculation Switch Signal
12 DK GRN 1163 APP Sensor 3 Signal
13 14 - - Not Used
15 BRN 25 Charge Indicator Control
16 GRY/BLK 1694 4WD Low Signal
17 DK GRN/WHT 2523 A/C Request Signal
18 - - Not Used
19 BLK/WHT 1695 Axle Switch Signal
20 LT GRN/BLK 822 VSS Low Signal
21 PPL/WHT 821 VSS High Signal
22 RED/BLK 1230 AT ISS High Signal
23 DK BLU/WHT 1231 AT ISS Low Signal
24 DK BLU 417 TP Sensor Signal
25 TAN 472 IAT Sensor Signal
26 PPL 2121 IC 1 Control
27 RED 2127 IC 7 Control
28 LT BLU/WHT 2126 IC 6 Control
29 DK GRN/WHT 2124 IC 4 Control
30 - - Not Used
31 YEL 492 MAF Sensor Signal
32 LT GRN 432 MAP Sensor Signal
33 DK GRN 1614 Recirculation Door Control
34 DK GRN/WHT 428 EVAP Canister Purge Solenoid Control
35 - - Not Used
36 BRN 436 AIR Pump Relay Control
37 38 - - Not Used
39 RED 631 12 Volt Reference
40 BLK/WHT 451 Ground
41 WHT 257 EGR Solenoid Control
42 - - Not Used
43 DK GRN/WHT 459 A/C Clutch Relay Control
44 PNK 1039 Ignition 1 Voltage
45 WHT 1310 EVAP Canister Vent Solenoid Control
46 BRN/WHT 419 MIL Control
47 YEL/BLK 1223 (2-3 Shift Solenoid or Shift Solenoid B) Valve Control
48 LT GRN 1222 (1-2 Shift Solenoid or Shift Solenoid A) Valve Control
49 YEL/BLK 1827 Vehicle Speed Signal
50 DK GRN/WHT 817 Vehicle Speed Signal
51 YEL/BLK 1227 TFT Sensor Signal
52 GRY 23 Generator Field Duty Cycle Signal
53 DK BLU 2687 Transmission MIL Request Signal
54 PPL 1589 Fuel Level Sensor Signal [- Primary]
55 DK GRN 603 A/C Low Pressure Switch Signal
56 - - Not Used
57 BLK 552 Low Reference
58 59 - - Not Used
60 BRN 2129 Low Reference
61 BRN/WHT 2130 Low Reference
62 GRY 773 Transmission Range Switch Signal C
63 PNK 1224 Transmission Fluid Pressure Switch Signal A
64 DK GRN 890 Fuel Tank Pressure Sensor Signal
65 - - Not Used
66 PPL/WHT 2128 IC 8 Control
67 RED/WHT 2122 IC 2 Control
68 DK GRN 2125 IC 5 Control
69 LT BLU 2123 IC 3 Control
70 71 - - Not Used
72 BLK/WHT 3122 HO2S Heater Return Signal
73 DK BLU 1936 Fuel Level Sensor Signal [- Secondary]
74 LT GRN/WHT 3213 HO2S Heater Supply Voltage
75 RED/WHT 3222 HO2S Heater Supply Voltage
76 79 - - Not Used
80 LT GRN 3212 HO2S Heater Return Signal
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