For 1990-2009 cars

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

### Engine Control Module (ECM) C1

#### Connector Part Information

- OEM: 15499466
- Service: 88988931
- Description: 73-Way F MX 123 Series (BK)

#### Terminal Part Information

- Pins: 73
- Terminal/Tray: 7116-4151-02/9
- Core/Insulation Crimp: C
- Release Tool/Test Probe: 12094430/J-35616-4A (PU)

- Pins: 1, 3-6, 13, 18, 21, 24, 25, 27, 30, 31, 34, 36, 37, 39, 41-44, 47, 49, 54-56, 58, 66-68
- Terminal/Tray: 33467-0003/23
- Core/Insulation Crimp: H/H
- Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

- Pins: 19, 20, 70
- Terminal/Tray: 33467-0005/23
- Core/Insulation Crimp: J/J
- Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

#### Engine Control Module (ECM) C1

Pin | Wire Color | Circuit No. | Function
--- | --- | --- | ---
1 | D-BU | 1161 | APP Sensor 1 Signal
2 | -- | -- | Not Used
3 | BN | 4 | Accessory Voltage
4 | PU | 420 | TCC Brake Switch/Cruise Control Release Signal
5 | D-GN | 335 | Low Speed Cooling Fan Relay Control
6 | L-GN/WH | 465 | Fuel Pump Relay Control (- Primary)
7-12 | -- | -- | Not Used
13 | BN | 5069 | Powertrain Relay Control
14-17 | -- | -- | Not Used
18 | L-BU | 1162 | APP Sensor 2 Signal
19 | PK/BK | 1039 | Ignition 1 Voltage
20 | RD/WH | 840 | Battery Positive Voltage
21 | PU | 1272 | Low Reference
22-23 | -- | -- | Not Used
24 | TN | 2759 | Low Reference
25 | OG/BK | 380 | A/C Refrigerant Pressure Sensor Signal
26 | -- | -- | Not Used
27 | BN/WH | 419 | MIL Control
28-29 | -- | -- | Not Used
30 | D-GN/WH | 459 | A/C Compressor Clutch Relay Control
31 | YE | 447 | Starter Relay Coil Control
32-33 | -- | -- | Not Used
34 | PU/WH | 6356 | VSS Signal Low
35 | -- | -- | Not Used
36 | BN/WH | 379 | Cruise Control Clutch Pedal Position Switch Signal (M86)
37 | YE | 492 | Mass Air Flow Sensor Signal
38 | -- | -- | Not Used
39 | PU | 1589 | Fuel Level Sensor Signal (+ Primary)
40 | -- | -- | Not Used
41 | BN | 1271 | Low Reference
42 | D-GN | 890 | Fuel Tank Pressure Sensor Signal
43 | TN/BK | 2500 | High Speed GMLAN Serial Data (+) (1)
44 | TN | 2501 | High Speed GMLAN Serial Data (-) (1)
45-46 | -- | -- | Not Used
47 | WH/BK | 1164 | 5-Volt Reference
48 | -- | -- | Not Used
49 | D-BU | 473 | Coolant Fan Relay Output - Coil
50-53 | -- | -- | Not Used
54 | BN/WH | 6354 | VSS Signal High
55 | L-BU | 20 | Stop Lamp Supply Voltage
56 | D-GN | 1433 | PNP/ Clutch Start Switch Signal (M86)
57 | -- | -- | Not Used
58 | TN | 472 | Intake Air Temperature Sensor Signal
59-65 | -- | -- | Not Used
66 | GY | 2709 | 5-Volt Reference
67 | TN | 1274 | 5-Volt Reference
68 | BN | 436 | Air Injection Reaction Pump Motor Relay Output - Coil
69 | -- | -- | Not Used
70 | WH | 1310 | EVAP Canister Vent Solenoid Control
71-72 | -- | -- | Not Used
73 | PK/BK | 5293 | Ignition 1 Voltage

### Engine Control Module (ECM) C2

#### Connector Part Information

- OEM: 15497996
- Service: 88988372
- Description: 73-Way F MX 123 Series (GY)

#### Terminal Part Information

- Pins: 73
- Terminal/Tray: See Terminal Repair Kit
- Core/Insulation Crimp: See Terminal Repair Kit
- Release Tool/Test Probe: See Terminal Repair Kit

- Pins: 5, 9, 13, 20, 22-24, 26, 30-31, 33, 35, 39, 41-43, 45-46, 49-51, 54, 58, 67
- Terminal/Tray: 33467-0005/23
- Core/Insulation Crimp: C
- Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

- Pins: 6-8, 10, 16, 32, 37-38, 40, 48, 53, 57, 59, 65-66, 68
- Terminal/Tray: 33467-0003/23
- Core/Insulation Crimp: C
- Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

#### Engine Control Module (ECM) C2

Pin | Wire Color | Circuit No. | Function
--- | --- | --- | ---
1-3 | -- | -- | Not Used
4 | TN | 2761 | Low Reference
5 | PU | 574 | Low Reference
6 | TN | 1744 | Fuel Injector (1) Control
7 | PK/BK | 1746 | Fuel Injector (3) Control
8 | L-BU/BK | 844 | Fuel Injector (4) Control
9 | BN | 2129 | Low Reference
10 | L-GN/BK | 1745 | Fuel Injector (2) Control
11-12 | -- | -- | Not Used
13 | GY/BK | 2704 | 5-Volt Reference
14-15 | -- | -- | Not Used
16 | YE | 581 | TAC Motor Control (1)
17-19 | -- | -- | Not Used
20 | TN | 5301 | Low Reference
21 | -- | -- | Not Used
22 | PU | 2121 | Ignition Control (1)
23 | L-BU | 2123 | Ignition Control (3)
24 | D-GN/WH | 2124 | Ignition Control (4)
25 | -- | -- | Not Used
26 | OG/WH | 2122 | Ignition Control (2)
27-29 | -- | -- | Not Used
30 | D-GN/WH | 428 | EVAP Canister Purge Solenoid Control
31 | OG | 225 | Generator Turn On Signal
32 | BN | 582 | TAC Motor Control (2)
33 | D-BU | 5300 | 5-Volt Reference
34 | -- | -- | Not Used
35 | GY | 6255 | 5-Volt Reference
36 | -- | -- | Not Used
37 | PU/WH | 3110 | Heated Oxygen Sensor High Signal Sensor 1
38 | PU/WH | 1668 | Heated Oxygen Sensor High Signal Sensor 2
39 | L-GN | 432 | Manifold Absolute Pressure Sensor Signal
40 | TN | 2752 | Low Reference
41 | PU/WH | 6256 | Low Reference
42 | TN | 2760 | Low Reference
43 | GY/WH | 23 | Generator Field Duty Cycle Signal
44 | -- | -- | Not Used
45 | YE | 573 | Crankshaft Position Sensor Signal
46 | OG | 5275 | CMP Sensor Signal
47 | -- | -- | Not Used
48 | TN/WH | 3111 | Heated Oxygen Sensor Low Signal Sensor 1
49 | OG/BK | 469 | Low Reference
50 | GY | 1716 | Knock Sensor Signal
51 | D-BU | 496 | Knock Sensor Signal
52 | -- | -- | Not Used
53 | GY | 2701 | 5-Volt Reference
54 | L-GN | 2867 | 5-Volt Reference
55-56 | -- | -- | Not Used
57 | D-GN | 485 | Throttle Position Sensor (1) Signal
58 | YE | 410 | Engine Coolant Temperature Sensor Signal
59 | PU | 486 | Throttle Position Sensor (2) Signal
60-64 | -- | -- | Not Used
65 | GY/WH | 3113 | Heated Oxygen Sensor Heater Low Control Sensor 1
66 | GY/WH | 1423 | Heated Oxygen Sensor Heater Low Control Sensor 2
67 | TN/BK | 231 | Oil Pressure Switch Signal
68 | TN/WH | 1669 | Heated Oxygen Sensor Low Signal Sensor 2
69-72 | -- | -- | Not Used
73 | BK/WH | 451 | Signal Ground