For 1990-2009 cars

Connector 1: | Engine Control Module (ECM) C1
Connector 2: | Engine Control Module (ECM) C2
Connector 3: | Engine Control Module (ECM) C3

### Engine Control Module (ECM) C1

#### Connector Part Information

- OEM: 13510837
- Service: N/A
- Description: 56-Way F Micro-Pack 64 Series (BK)

#### Engine Control Module (ECM) C1

Pin | Wire | Circuit | Function
--- | --- | --- | ---
1-6 | -- | -- | Not Used
7 | WH | 17 | Brake Pedal Feed
8 | -- | -- | Not Used
9 | BK | 452 | Low Reference
10-11 | -- | -- | Not Used
12 | BN/WH | 419 | Malfunction Indicator Lamp
13 | D-GN/WH | 465 | Fuel Pump Relay
14-17 | -- | -- | Not Used
18 | YE/BK | 5278 | ECM/TCM Serial Data Wake-Up
19 | PK | 239 | Ignition Voltage
20 | RD/WH | 1440 | Battery Positive Voltage
21-32 | -- | -- | Not Used
33 | WH/BK | 1164 | 5-Volt Feed
34 | GY | 596 | 5-Volt Feed
35 | TN | 1274 | 5-Volt Feed
36 | BN | 1271 | Low Reference
37 | PU | 1272 | Low Reference
38 | -- | -- | Not Used
39 | BN | 818 | Vehicle Speed Signal
40 | BN | 5069 | Engine Relay
41-43 | -- | -- | Not Used
44 | D-BU | 1936 | Fuel Tank Oil Level Sensor 1
45 | L-BU | 1937 | Fuel Tank Oil Level Sensor 2
46 | -- | -- | Not Used
47 | D-BU | 1161 | APP Sensor 1
48 | D-GN | 890 | Fuel Tank Pressure Signal
49 | L-BU | 1162 | APP Sensor 2
50-52 | -- | -- | Not Used
53 | D-GN/WH | 459 | A/C Clutch Control
54 | D-BU | 473 | Fan Control 2
55 | WH | 1310 | Fuel Tank Emission
56 | YE | 447 | Active Control

### Engine Control Module (ECM) C2

#### Connector Part Information

- OEM: 15499466
- Service: N/A
- Description: 73-Way F 108-A (BK)

#### Engine Control Module (ECM) C2

Pin | Wire | Circuit | Function
--- | --- | --- | ---
1 | PU | 2121 | Ignition Coil 1
2 | TN/WH | 3111 | Oxygen Sensor A Low
3 | PU/WH | 3110 | Oxygen Sensor A High
4 | PU | 3120 | Oxygen Sensor C High
5 | TN | 3121 | Oxygen Sensor C Low
6 | L-BU | 1876 | Knock Sensor Bank 2
7 | GY | 2303 | KS Low Reference Bank 2
8 | D-BU | 496 | Knock Sensor Bank 1
9 | GY | 1716 | KS Low Reference Bank 1
10 | -- | -- | Not Used
11 | YE | 581 | Throttle Motor Positive Rotate
12 | BN | 582 | Throttle Motor Negative Rotate
13 | PK/BK | 5290 | Engine Relay Control
14 | PK/BK | 6395 | Camshaft Phasing Control 2
15 | TN/BK | 6397 | Camshaft Phasing Control 4
16 | D-BU/WH | 878 | Fuel Injector 8 Control
17 | OG/WH | 2122 | Ignition Coil 2
18 | L-BU/WH | 2126 | Ignition Coil 6
19 | BN/WH | 2130 | Low Reference 2
20 | PU | 6267 | Low Reference
21 | TN | 6268 | Low Reference
22 | WH | 6269 | Low Reference
23 | BN | 6266 | Low Reference
24 | BK | 2755 | Low Reference
25-26 | -- | -- | Not Used
27 | GY/BK | 6272 | Low Reference
28 | PK/BK | 5290 | Engine Relay Control
29 | TN | 2752 | Low Reference
30 | BN/WH | 6754 | Camshaft Position Phasing Control 3 Low Reference
31 | BU/WH | 6756 | Camshaft Phasing Control 1 Low Reference
32 | L-BU/BK | 1746 | Fuel Injector 3 Control
33 | OG | 2127 | Ignition Coil 7
34 | D-GN | 2125 | Ignition Coil 5
35 | BN | 2129 | Low Reference (1)
36 | D-GN | 6457 | 5-Volt Feed
37 | OG | 6260 | 5-Volt Feed
38 | PK | 6261 | 5-Volt Feed
39 | D-BU | 6259 | 5-Volt Feed
40 | GY | 2705 | 5-Volt Feed
41 | -- | -- | Not Used
42 | BK | 2760 | Low Reference
43 | PU/WH | 6270 | 5-Volt Feed
44 | GY | 2701 | Feed
45 | -- | -- | Not Used
46 | BN | 6753 | Camshaft Position Phasing Control 2 Low Reference
47 | D-BU | 6755 | Camshaft Position Phasing Control 4 Low Reference
48 | L-BN/BK | 1745 | Fuel injector 2 Control
49 | TN/WH | 845 | Fuel injector 5 Control
50 | WH/BK | 6396 | Camshaft Position Phasing Control 3
51 | GY/BK | 6394 | Camshaft Position Phasing Control 1
52 | L-BU/BK | 844 | Fuel Injector 4 Control
53 | L-BU | 2123 | Ignition Coil 3
54 | D-GN/WH | 2124 | Ignition Coil 4
55 | PU/WH | 2128 | Ignition Coil 8
56 | D-GN/WH | 6264 | Camshaft Position Sensor X
57 | OG/BK | 6263 | Camshaft Position Sensor Y
58 | PK/BK | 6262 | Camshaft Position Sensor Z
59 | D-BU/WH | 6265 | Camshaft Position Sensor W
60 | TN/WH | 331 | Engine Oil Pressure Signal
61 | -- | -- | Not Used
62 | TN | 472 | IAT Signal
63 | WH/BK | 6271 | Crankshaft Position Sensor
64 | D-GN | 485 | Throttle Position Sensor
65 | -- | -- | Not Used
66 | PU | 486 | TP Sensor 2
67 | YE | 492 | Air Quality Signal
68 | GY/WH | 3113 | Oxygen Sensor A Heat
69 | BK/WH | 3122 | Oxygen Sensor C Heat
70 | YE/BK | 846 | Fuel Injector 6 Control
71 | OG/BK | 877 | Fuel Injector 7 Control
72 | TN | 1744 | Fuel Injector 1 Control
73 | BK/WH | 1551 | Ground

### Engine Control Module (ECM) C3

#### Connector Part Information

- OEM: 15497996
- Service: N/A
- Description: 73-Way F 105-B (BK)

#### Engine Control Module (ECM) C3

Pin | Wire | Circuit | Function
--- | --- | --- | ---
1-2 | -- | -- | Not Used
3 | TN/WH | 3211 | Oxygen Sensor B Low
4 | PU/WH | 3210 | Oxygen Sensor B High
5 | PU | 3220 | Oxygen Sensor D High
6 | TN | 3221 | Oxygen Sensor D High
7 | OG | 225 | Alternator Output-Regulator Reference Voltage
8-14 | -- | -- | Not Used
15 | L-GN | 3212 | Oxygen Sensor B Heat
16-20 | -- | -- | Not Used
21 | BK/WH | 452 | Low Reference
22 | -- | -- | Not Used
23 | OG/BK | 469 | Low Reference
24-28 | -- | -- | Not Used
29 | GY | 23 | Alternator Field Duty Cycle Signal
30-32 | -- | -- | Not Used
33 | TN | 2501 | Low Speed GMLAN Serial Data (1) (T43)
34 | -- | -- | Not Used
35 | TN | 2761 | Low Reference
36 | -- | -- | Not Used
37 | GY | 596 | Feed
38 | -- | -- | Not Used
39 | GY | 2704 | Feed
40-45 | -- | -- | Not Used
46 | OG/BK | 1786 | Clutch Activate
47 | -- | -- | Not Used
48 | D-GN/WH | 428 | Evaporative Emission Canister Purge Solenoid Valve
49 | D-GN | 335 | Fan Control (1)
50 | OG/WH | 3223 | Oxygen Sensor D Heat
51-52 | -- | -- | Not Used
53 | TN/BK | 2500 | High Speed GMLAN Serial Data (1) (T43)
54 | -- | -- | Not Used
55 | YE | 410 | ECT Signal
56 | -- | -- | Not Used
57 | OG/BK | 380 | A/C Pressure Sensor
58 | -- | -- | Not Used
59 | L-GN | 432 | Intake Manifold Pressure Sensor
60-72 | -- | -- | Not Used
73 | BK/WH | 1551 | Ground