WWW.LT1SWAP.COM
Visit my Facebook page for a lot of New Pictures & Harness Guides YouTube channel for How To videos - E-Mail: brendan@lt1swap.com ph. 417-277-5836
For detailed information on modifying your F-Body LT1 wiring harness, please see this page on my Facebook page.
1994 LT1 F-Body Harness Rework Detailed Instructions - Facebook photo album containing step by step pictures with details.
These schematics are specifically for 1994 Camaro, Firebird 5.7L LT1. however, will be very similar to 1995.
shell over wires opens, allowing access to pin cavity.
label wires needed for external connection. Here two 12v+ key power feeds are labeled.
I relocate passanger side o2, knock, and eng ground wires to allow more length to locate pcm.
this requires adding length to the tan/purple o2 sensor wires, as well as knock sensor, and I move engine ground to back of head, does not need longer
sort wires for fuse block, and for other connections, diag port, check engine light, brake sw, etc.
fuse block added to harness.
PCM Connector Pinouts are specifically for 1997 LT1 5.7L Camaro/Firebird, however, 94-97 all share almost the same pinout. 96-97 will have additional wiring for OBD2 stuff, like rear oxygen sensors, crank shaft position sensor, evap vacuum switch.
| Connector C1 32 Pin Connector (Red) | ||||||
|---|---|---|---|---|---|---|
| Pin | Wire Color | Circuit No. | Function | Component Connector Cavity | DTC(s) Affected | Possible Symptoms From a Faulty Circuit |
| 1 | Lt Blu/Blk | 647 | Crankshaft Position Sensor Signal | CKP C | P0335, P0336 | Misfire diagnostic inoperative |
| 2 | Blk/Wht | 451 | PCM Ground | Engine Ground * | Engine cranks but will not start. | |
| 3 | Blk | 1744 | Injector #1 Control | Injector #1 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 4 | Lt Blu/Blk | 844 | Injector #4 Control | Injector #4 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 5 | Yel/Blk | 846 | Injector #6 Control | Injector #6 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 6 | Red/Blk | 877 | Injector #7 Control | Injector #7 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 7 | Dk Grn/Wht | 465 | FP Relay Control | FP Relay B2 | Long Crank Time Before Engine Starts | |
| 8 | Not Used | |||||
| 9 | Lt Blu | 697 | EGR Vacuum Control signal solenoid valve | EGR Solenoid B | P0400 P0403 (3) | Detonation, Stall, Rough Idle, And Poor Performance |
| 10 | Dk Blu | 473 | Cooling fan relay #2 and #3 control | Fan Relays 86 | P1642 (3) | Inoperative Cooling Fan Or Fan ON At All Times |
| 11 | Dk Grn | 335 | Cooling Fan relay #1 Control | Fan Relay 86 | P1641 (3) | Inoperative Cooling Fan Or Fan ON At All Times |
| 12 | Not Used | |||||
| 13 | Wht | 121 | Engine Speed Output Signal | * | P1643 (3) | Tach inoperative |
| 14 | Brn | 436 | AIR Pump Relay Control | AIR Pump Relay 86 | P0412 (3) | AIR Pump Inoperative or ON at All Times. |
| 15-17 | Not Used | |||||
| 18 | Blk/Wht | 451 | PCM Ground | Engine Ground * | Engine cranks but will not start. | |
| 19 | Lt Grn /Blk | 1745 | Injector #2 Control | Injector #2 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 20 | Blk/Wht | 845 | Injector #5 Control | Injector #5 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 21 | Pnk/Blk | 1746 | Injector #3 Control | Injector #3 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 22 | Dk Blu/Wht | 878 | Injector #8 Control | Injector #8 A | P0200 (3) P1222 | Rough idle, Engine miss |
| 23-30 | Not Used | |||||
| 31 | Ppl | 401 | VSS Signal Low | VSS A | P0500 P0502 P0503 P1652 (1) | Inoperative Speedometer, Inoperative Cruise Control, Radio Volume will not increase with vehicle Speed, Transmission Restricted to second Gear. |
| 32 | Yel | 400 | VSS Signal High | VSS B | P0500 P0502 P0503 P1652 (1) | Inoperative Speedometer, Inoperative Cruise Control, Radio Volume will not increase with vehicle Speed, Transmission Restricted to second Gear. |
| PCM Connector C2 (Black) | ||||||
|---|---|---|---|---|---|---|
| Pin | Wire Color | Circuit No. | Function | Component Connector Cavity | DTC(s) Affected | Possible Symptoms From a Faulty Circuit |
| 1 | Dk Grn/Wht | 762 | A/C Request Signal | A/C Pressure cycling switch B | A/C Inoperative (1) A/C ON at all times | |
| 2 | Red/Blk | 453 | Low Resolution Signal | Test Connector A Distributor A | P1371 (3) | Engine Cranks But Will Not Start (1) |
| 3 | Pnk/Blk | 632 | Distributor Reference Low Signal | Test Connector D Distributor D | Engine Cranks But Will Not Start (1) | |
| 4 | Not Used | |||||
| 5 | Wht | 423 | Ignition Control | Ignition Coil Module B | P1351 (1,4) P1361 (2) | Engine Cranks But Will Not Start (1) |
| 6 | Blk | 470 | Sensor Ground | ECT A, TP B, EOT A Trans M, EBTCM | P0118 (1) P0122 (1) P1118 (1) P0713 (1) P1188 | Lack of Power, Rough Idle, High Idle and TCC May Not Apply Properly |
| 7 | Lt Grn | 1222 | Transmission 1-2 Shift Solenoid control | Trans A | P0753 (3,4) | Second and Third Gear, or Forth Gear Only |
| 8 | Dk Grn/Wht | 817 | VSS Output | Cruise module, CCM, Radio | P1652 (3,4) | Speedometer Inoperative Cruise Inoperative |
| 9-11 | Not Used | |||||
| 12 | Yel/Blk | 1223 | Transmission 2-3 Shift Solenoid control (LT1 Only) | Trans B | P0758 (3,4) | Second or Third Gear Only, No TCC Apply |
| 13 | Brn or Gry | 897 or 324 | Transmission 3-2 Shift Solenoid control (LT1 Only) or 2nd and 3rd Gear Blockout Relay Control (LT4 Only) | Trans S or 2nd and 3rd gear blockout relay 30 | P0785 (3,4) or P1657 | Harsh 3-2 Downshift, Third Gear Only Or Will Not Blockout 2nd and 3rd Gear or 1st to 4th Gear Only |
| 14 | Red | 631 | Distributor Ignition Feed | Test Connector C Distributor C | Engine Cranks But Will Not Start | |
| 15 | Red | 142 | PCM Battery Feed | * | * | Engine Cranks But Will Not Start |
| 16 | Blk | 452 | Sensor Ground | MAP A IAT A, A/C refrigerant pressure sensor A | P0113 (1) P0108 (1) P0530 (1) | Poor Performance, A/C Inoperative |
| 17-18 | Not Used | |||||
| 19 | Yel | 492 | MAF Sensor Signal | MAF A | P0100 P0101 P0102 (2) P0103 | Engine Stall, Hesitation When Malfunction Occurs |
| 20 | Ppl/Wht | 430 | High Resolution Signal | Test Connector B Distributor B | P1372 (3,4) | Engine Surge, Lack of Power |
| 21 | Dk Grn | 59 | A/C Clutch Status | A/C clutch relay 30 A/C clutch A | P1539 (4) P1546 (1) | A/C Inoperative |
| 22 | Lt Blu/Blk | 396 | Cruise Active signal | Cruise Control Module | modified Transmission Shift Patterns | |
| 23 | Lt Blu | 997 | EVAP Vacuum Switch | EVAP Vacuum Switch B | P0441 P1441 | |
| 24-27 | Not Used | |||||
| 28 | Gry | 474 | 5 Volt reference | TP A, EBTCM | P0123 (3) | High Idle, Lack of Performance |
| 29 | Gry | 416 | 5 Volt reference | MAP C, A/C Refrigerant Pressure Sensor B | P0107 (3) P0530 (3) | A/C Inoperative |
| 30 | Pnk | 239 | PCM Ignition Feed | * | Engine Cranks But Will Not Start | |
| 31 | Red | 142 | PCM Battery Feed | * | ||
| 32 | Not Used | |||||
| PCM Connector C3 (Clear or Gray) | ||||||
|---|---|---|---|---|---|---|
| Pin | Wire Color | Circuit No. | Function | Component Connector Cavity | DTC(s) Affected | Possible Symptoms From a Faulty Circuit |
| 1 | Lt Blu/Wht | 1747 | IAC Coil A High | IAC D | P0506 P0507 P1508 P1509 | Incorrect Idle, Surge, Stall |
| 2 | Lt Blu/Blk | 1748 | IAC Coil A Low | IAC C | P0506 P0507 P1508 P1509 | Incorrect Idle, Surge, Stall |
| 3 | Tan | 1671 | Bank 2 (Right Rear) HO2S #2 Low | HO2S A | ||
| 4 | Ppl | 1670 | Bank 2 (Right Rear) HO2S #2 High | HO2S B | ||
| 5 | Lt Grn/Blk | 444 | IAC Coil B Low | IAC A | P0506 P0507 P1508 P1509 | Incorrect Idle, Surge, Stall |
| 6 | Lt Grn/Wht | 1749 | IAC Coil B High | IAC B | P0506 P0507 P1508 P1509 | Incorrect Idle, Surge, Stall |
| 7 | Tan | 1667 | Bank 2 (Right Front) HO2S #2 Low | HO2S A | P0154 (1) | Rough Idle, Lean Exhaust, Poor Performance and Poor Fuel Economy |
| 8 | Ppl | 1666 | Bank 2 (Right Front) HO2S #2 High | HO2S B | P0151 (2) P0152 (4) | |
| 9-10 | Not Used | |||||
| 11 | Lt Grn | 981 | ASR Active Signal | * | P1572 | |
| 12 | Gry/Blk | 1687 | ASR Spark Retard Signal | * | Poor Performance, ABS/TCS DTC 73 | |
| 13 | Not Used | |||||
| 14 | Ppl | 420 | Brake Switch Signal | Brake Switch A | P0703 (3,4) | No TCC |
| 15 | Orn/Blk | 434 | PNP Switch | PNP Switch B | Poor Fuel Economy, Stall, Incorrect Idle | |
| 16 | Red/Blk | 1228 | Transmission Pressure Control Solenoid | Transmission C | P0748 (3) | Harsh Transmission Shift |
| 17 | Tan/Wht | 1669 | Bank 1 (Left Rear) HO2S #2 Low | HO2S A | P0140 (1) | |
| 18 | Ppl/Wht | 1668 | Bank 1 (Left Rear) HO2S #2 High | HO2S B | P0137 P0138 P0140 | |
| 19 | Tan/Wht | 1653 | Bank 1 (Left Front) HO2S #1 Low | HO2S B | P0134 (1) | Rough Idle, Lean Exhaust, Poor Performance and Poor Fuel Economy |
| 20 | Ppl/Wht | 1665 | Bank 1 (Left Front) HO2S #1 High | HO2S B | P0131 (2) P0132 (4) P0134 (1) | Rough Idle, Lean Exhaust, Poor Performance and Poor Fuel Economy |
| 21 | Tan | 472 | IAT Sensor Signal | IAT B | P0113 (1) P0122 (2) P1111 (2) P1112 (1) | Poor Fuel Economy |
| 22 | Dk Blu | 417 | TP Sensor Signal | TP Sensor C | P0121 P0122 (4) P0123 (3) P1121 (3) P1122 (4) | High Idle, Lack of Power, Harsh Transmission Shifts |
| 23 | Lt Grn | 432 | MAP Sensor Signal | MAP B | P0106 P0107 (3) P0108 (4) P1106 (4) P1107 (3) | Modified Shift Patterns |
| 24 | Not Used | |||||
| 25 | Yel | 410 | ECT Sensor Signal | ECT B | P0117 (2) P0118 (1) P0125 P1114 (2) P1114 (1) | Exhaust Odor, Rough Idle, Poor Fuel Economy, TCC Apply Cold |
| 26-27 | Not Used | |||||
| 28 | Pnk | 1224 | Transmission Range Signal A | Transmission N | P1810 (3) | No TCC, Harsh Shift |
| 29 | Dk Blu | 1225 | Transmission Range Signal B | Transmission R | P1810 (3) | No TCC, Harsh Shift |
| 30 | Red | 1226 | Transmission Range C | Transmission P | P1810 (3) | No TCC, Harsh Shift |
| 31 | Not Used | |||||
| 32 | Blk/Whit | 451 | PCM Ground | Engine Block | Engine Cranks But Will Not Run | |
| PCM Connector C4 (Blue) | ||||||
|---|---|---|---|---|---|---|
| Pin | Wire Color | Circuit No. | Function | Component Connector Cavity | DTC(s) Affected | Possible Symptoms From a Faulty Circuit |
| 1 | Blk/Wht | 451 | PCM Ground | Engine Block | Engine Cranks But Will Not Run | |
| 2 | Lt Blu/Wht | 1229 | Transmission Pressure Control Solenoid Low | Transmission D | P0748 (3) | Harsh Transmission Shifts |
| 3 | Pnk | 239 | PCM Ignition Feed | * | Engine Cranks But Will Not Run | |
| 4-5 | Not Used | |||||
| 6 | Brn | 418 | Transmission TCC PWM Solenoid | Transmission U | TCC Inoperative | |
| 7 | Ppl | 1807 | Serial Data (Class 2) | DLC 2 | No Scan Tool Communications | |
| 8 | Dk Grn/Wht | 459 | A/C Cutch Control | A/C Clutch Relay 86 | P1545 P1539 | A/C Clutch Inoperative, A/C on At All Times |
| 9 | Brn/Wht | 419 | MIL Control | * | P1661 | MIL On All Times or MIL Inoperative |
| 10 | Dk Grn/Wht | 428 | EVAP Canister Purge Solenoid Valve Control | EVAP Canister Purge Solenoid Valve B | P0443 P0441 | Purge Inoperative or Purge On All The Time |
| 11 | Tan/Blk | 422 | Transmission TCC Solenoid | Transmission T | TCC Inoperative or On All The Time | |
| 12 | Red/Blk | 380 | A/C Refrigerant Pressure Sensor Signal | A/C Refrigerant Pressure Sensor C | P0530 | A/C Inoperative |
| 13-14 | Not Used | |||||
| 15 | Wht | 375 | 1-4 Upshift Lamp Control | 1 to 4 Upshift Lamp | P1664 | A/C Inoperative |
| 16-19 | Not Used | |||||
| 20 | Wht/Blk | 448 | Output/Field Service Enable | DLC 6 Low Pressure Tire Module | ||
| 21 | Lt Blu | 1876 | Bank 1 (Left) Knock Sensor (KS) Signal | Left Knock Sensor | P0327 (3) | Lack of Performance or Detonation |
| 22 | Dk Blu | 496 | Bank 2 (Right) Knock Sensor (KS) Signal | Right Knock Sensor | P0332 (3) | Lack of Performance or Detonation |
| 23-25 | Not Used | |||||
| 26 | Dk Grn/Wht | 357 | Engine Oil Temperature Sensor Signal | EOT B | P1187 P1188 | |
| 27 | Not Used | |||||
| 28 | Yel/Blk | 1227 | Transmission Fluid Temperature Sensor Signal | Transmission L | P0712 P1188 | Early or Delayed Transmission Shifts |
| 29 | Tan | 800 | Serial Data (UART) | * | ||
| 30 | Tan | 800 | Serial Data (UART) | * | ||
| 31-32 | Not Used | |||||