2005 Buick Century LimitedFACTORY OEM SERVICE PROCEDURE

Powertrain Control Module (PCM) Connector End Views

Powertrain Control Module (PCM) Connector C1

GM73173Courtesy of GENERAL MOTORS CORP.
Connector Part Information
  • 12191110
  • 80-Way F Micro-Pack 100W Series, Sealed (BLU)
Pin Wire Color Circuit No. Function
1 BLK 2762 Low Reference
2-3 - - Not Used
4 LT GRN 1222 1-2 Shift Solenoid Valve Control
5 DK BLU 473 High Speed Cooling Fan Relay Control
6 DK GRN 335 Low Speed Cooling Fan Relay Control
7 BRN/WHT 633 CMP Sensor Signal
8 PPL/WHT 430 Low Resolution Engine Speed Signal
9 LT BLU/BLK 647 Medium Resolution Engine Speed Signal
10 GRY 2704 5-Volt Reference
11 - - Not Used
12 BLK 808 HO2S Low Signal
13 ORN/ BLK 469 Low Reference
14-15 - - Not Used
16 BLK/WHT 451 Ground
17 BLK 2760 Low Reference
18 - - Not Used
19 PPL 1500 Ignition 0 Voltage
20 ORN 540 Battery Positive Voltage
21-27 - - Not Used
28 BLK 808 HO2S Low Signal
29 BLK 808 Low Reference
30 PPL 420 TCC Brake Switch/Cruise Control Release Signal
31 BLK 2753 Low Reference
32 GRY 435 EGR Solenoid Low Control
33 DK BLU 496 KS 1 Signal
34-37 - - Not Used
38 LT GRN/WHT 1749 IAC Coil B High Control
39-42 - - Not Used
43 BLK 1744 Fuel Injector 1 Control
44 YEL/BLK 1223 2-3 Shift Solenoid Valve Control
45 - - Not Used
46 PNK/BLK 1746 Fuel Injector 3 Control
47 LT GRN/BLK 1745 Fuel Injector 2 Control
48 RED/BLK 453 Low Reference
49-52 - - Not Used
53 TAN/BLK 424 IC Timing Signal
54 WHT 423 IC Timing Control
55 DK GRN/WHT 817 Vehicle Speed Signal
56 BLK/WHT 451 Ground
57 BLK/WHT 451 Ground
58 DK GRN 1049 PCM Class 2 Serial Data
59 - - Not Used
60 BLK/WHT 451 Ground
61 BLK 2752 Low Reference
62 DK BLU/WHT 1231 AT ISS Low Signal
63 RED/BLK 1230 AT ISS High Signal
64 YEL 400 Signal High-Front
65 PPL 401 Signal Low-Front
66-67 - - Not Used
68 YEL 772 Transmission Range Signal B
69 YEL 492 MAF Sensor Signal
70-71 - - Not Used
72 DK GRN 83 Cruise Control Inhibit Signal
73 BLK/WHT 845 Fuel Injector 5 Control
74-75 - - Not Used
76 DK GRN/WHT 428 EVAP Canister Purge Solenoid Valve Control
77-78 - - Not Used
79 YEL/BLK 846 Fuel Injector 6 Control
80 BLK 2751 Low Reference
Powertrain Control Module (PCM) Connector C2

GM73173Courtesy of GENERAL MOTORS CORP.
Connector Part Information
  • 12191110
  • 80-Way F Micro-Pack 100 W Series, Sealed (CLR)
Pin Wire Color Circuit No. Function
1 - - Not Used
2 WHT 1310 EVAP Canister Vent Solenoid Valve Control
3 DK GRN/WHT 465 Fuel Pump Relay Control
4 WHT 257 EGR Solenoid High Control
5 BRN/WHT 419 MIL Control
6 - - Not Used
7 LT BLU/WHT 1747 IAC Coil A High Control
8-9 - - Not Used
10 PPL 412 HO2S High Signal
11 PPL/WHT 1668 HO2S High Signal
12-15 - - Not Used
16 WHT 776 Transmission Range Signal P
17 - - Not Used
18 BLK/WHT 771 Transmission Range Signal A
19 TAN/BLK 231 Oil Pressure Switch Signal
20-21 - - Not Used
22 DK GRN/WHT 762 A/C Request Signal (CJ3)
23 PPL 806 Crank Voltage
24 PNK 439 Ignition 1 Voltage
25 LT GRN 432 MAP Sensor Signal
26 YEL 410 ECT Sensor Signal
27 RED/BLK 380 A/C Refrigerant Pressure Sensor Signal
28 BRN 1456 EGR Valve Position Signal
29 - - Not Used
30 GRY/BLK 2702 5-Volt Reference
31-32 - - Not Used
33 GRY 2701 5-Volt Reference
34 GRY 474 5-Volt Reference
35 BLK 452 Low Reference
36 - - Not Used
37 BLK/WHT 3113 HO2S Heater Low Control
38 - - Not Used
39 DK GRN/WHT 459 A/C Compressor Clutch Relay Control
40-41 - - Not Used
42 LT BLU/BLK 844 Fuel Injector 4 Control
43 - - Not Used
44 LT BLU/BLK 1748 IAC Coil A Low Control
45 RED/BLK 1228 PC Solenoid Valve High Control Sol. A
46 LT BLU/WHT 1229 PC Solenoid Valve Low Control Sol. A
47 - - Not Used
48 BLK 808 HO2S Heater Low Control
49 LT GRN/BLK 444 IAC Coil B Low Control
50 TAN 472 IAT Sensor Signal
51-54 - - Not Used
55 DK GRN 890 Fuel Tank Pressure Sensor Signal
56 GRY 773 Transmission Range Signal C
57- 58 - - Not Used
59 WHT 85 Cruise Control Engaged Signal
60 - - Not Used
61 RED 225 Generator Turn ON Signal
62 - - Not Used
63 YEL 657 TCC Release Switch Signal
64-65 - - Not Used
66 DK BLU 417 TP Sensor Signal
67 - - Not Used
68 YEL/BLK 1227 TFT Sensor Signal
69 PPL 1589 Fuel Level Sensor Signal
70 LT GRN 1867 12-Volt Reference
71 - - Not Used
72 RED/WHT 812 12-Volt Reference
73 BLK 407 Low Reference
74 YEL/BLK 1868 Low Reference
75 BRN 436 AIR Pump Relay Control (Not Used)
76 YEL/BLK 625 Starter Enable Relay Control
77 - - Not Used
78 BRN 418 TCC PWM Solenoid Valve Control
79-80 - - Not Used
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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • 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.
  • • You are not confident in the next step or safety outcome.

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