2004 Chevrolet SSRFACTORY OEM SERVICE PROCEDURE

Powertrain Control Module (PCM) Connectors

WARNING: This page is about a different car, the 2004 GMC Yukon XL, 2004 Chevrolet Suburban, and 2004 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
Powertrain Control Module (PCM) - C1

GM655733Courtesy of GENERAL MOTORS CORP.
Connector Part Information
  • 12191489
  • 80-Way F Micro-Pack 100W Sealed (BLU)
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
5-6 - - Not Used
7 GRY 2705 5-Volt Reference
8-10 - - 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
15 DK BLU/
WHT		 774 UART Serial Data
16-17 - - Not Used
18 DK GRN 1433 Clutch Start Switch Signal (M/T)
19 PNK 439 Ignition 1 Voltage
20 ORN 440 Battery Positive Voltage
21 YEL/BLK 1868 Low Reference
22 LT GRN 488 PTO Enable Switch (w/PTO)
23 BLK 470 Low Reference
24 BLK/WHT 451 Ground
25 TAN 1671 HO2S Low Signal Bank 2 Sensor 2 (w/NC1)
26 TAN 1677 HO2S Low Signal Bank 2 Sensor 1
27 BLK/WHT 451 Ground
28 TAN 1669 HO2S Low Signal Bank 1 Sensor 2 (w/NC1)
29 TAN 1664 HO2S Low Signal Bank 1 Sensor 1
30 LT GRN 1478 Coolant Level Switch Signal
31-32 - - Not Used
33 PPL 420 TCC Brake Switch/Cruise Control Release Signal
34 ORN/BLK 1786 Park/Neutral Signal (Allison Transmission Only)
35 GRY 48 CPP Switch Signal (M/T)
36 BLK 1744 Fuel Injector 1 Control
37 YEL/BLK 846 Fuel Injector 6 Control
38 - - Not Used
39 YEL/BLK 625 Starter Enable Relay Control
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 2700 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 Knock Sensor 1 Signal
52 YEL 2522 PTO Status (w/PTO)
53 - - Not Used
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 PCM Class 2 Serial Data
59 YEL 710 Class 2 Serial Data
60 - - Not Used
61 PNK/BLK 632 Low Reference
62 - - Not Used
63 BLK 2755 Low Reference
64 BLK/WHT 451 Ground
65 PPL 1670 HO2S High Signal Bank 2 Sensor 2 (w/NC1)
66 PPL 1666 HO2S High Signal Bank 2 Sensor 1
67 BLK/WHT 451 Ground
68 PPL/WHT 1668 HO2S High Signal Bank 1 Sensor 2 (w/NC1)
69 PPL/WHT 1665 HO2S High Signal Bank 1 Sensor 1
70 BRN 1174 Oil Level Switch Signal
71 LT BLU 494 PTO Engine Kill (w/PTO)
72 - - Not Used
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 PTO Engage (w/PTO)
79 - - Not Used
80 BLK 407 Low Reference
Powertrain Control Module (PCM) - C2

GM684875Courtesy of GENERAL MOTORS CORP.
Connector Part Information
  • 12191488
  • 80-Way F Micro-Pack 100W Sealed (RED)
Pin Wire Color Circuit No. Function
1 BLK/WHT 451 Ground
2 WHT 2467 Torque Response Reply Signal (Allison Trans Only)
3 TAN 1465 Fuel Pump Relay Control - Secondary
4 - - Not Used
5 TAN/BLK 464 Delivered Torque Signal (Allison Trans Only)
6 - - Not Used
7 RED 1676 EGR Valve Supply Voltage
8 - - Not Used
9 DK GRN/
WHT		 465 Fuel Pump Relay Control
10 WHT 121 Engine Speed Signal
11 - - Not Used
12 DK BLU 2466 Trans MIL Request Signal (Allison Trans Only)
13 - - Not Used
14 RED/BLK 380 A/C Refrigerant Pressure Sensor Signal
15 BRN 25 Charge Indicator Control
16 GRY/BLK 1694 4WD Low Signal (w/4WD)
17-18 - - Not Used
19 BLK/WHT 1695 Axle Switch Signal (w/NP2)
20 LT GRN/BLK 822 VSS Low Signal
21 PPL/WHT 821 VSS High Signal (Except Allison Transmission
YEL 400 Signal High - Front (Allison Trans Only)
22-24 - - Not Used
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 - - Not Used
34 DK GRN/
WHT		 428 EVAP Canister Purge Solenoid Control
35-38 - - 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 Compressor Clutch Relay Control
44 - - Not Used
45 WHT 1310 EVAP Canister Vent Solenoid Control
46 BRN/WHT 419 MIL Control
47-48 - - Not Used
49 YEL/BLK 1827 Vehicle Speed Signal
50 DK GRN/
WHT		 817 Vehicle Speed Signal
51 - - Not Used
52 BRN 2391 HO2S Heater Low Control Bank 1 Sensor 2 (W/NC1)
53 RED/WHT 3223 HO2S Heater Low Control Bank 2 Sensor 2 (W/NC1)
54 PPL 1589 Fuel Level Sensor Signal
55-56 - - Not Used
57 BLK 552 Low Reference
58 TAN/WHT 332 Oil Pressure Sensor Signal
59 PPL 806 Crank Voltage
60 BRN 2129 Low Reference
61 BRN/WHT 2130 Low Reference
62-63 - - Not Used
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 Low Control Bank 1 Sensor 2 (w/NC1)
73 DK BLU 1936 Fuel Level Sensor Signal - Secondary
74 LT GRN/WHT 3213 HO2S Heater Low Control Bank 2 Sensor 1
75-79 - - Not Used
80 BLK 2751 Low Reference
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  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
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