How to use this page
The FG Barra plug-in uses two connectors, A and B, with 46 pins each. Haltech lists them in pin order, which is handy when you have the plug in your hand and useless when you are asking "where does injector 3 go?". Below, the same information is sorted by system. Pins marked for turbo or non-turbo models only are noted, and a few pins exist in the factory plug but are not used by the Haltech.
This applies to the Elite plug-in for FG, such as the Elite 2500 FG Barra kit. BA and BF models have their own pinouts, so use the BA pinout or BF pinout for those cars.
Injectors and ignition
| Function | Pin(s) | Notes |
|---|---|---|
| Injector 1 / 2 / 3 | A14 / A07 / A15 | |
| Injector 4 / 5 / 6 | A04 / A08 / A03 | |
| Ignition 1 / 2 / 3 | A35 / A46 / A12 | Coil-on-plug outputs |
| Ignition 4 / 5 / 6 | A34 / A24 / A23 |
If you are running the factory coils on a wire-in or terminated setup, Haltech's FG ignition harness for OEM coils matches this layout.
Crank, cam and variable cam timing
| Function | Pin(s) | Notes |
|---|---|---|
| Crank sensor + / - | A30 / A41 | Twist this pair and keep it away from coil wiring |
| Cam sensor 1 | A31 | |
| Cam sensor 2 | A33 | |
| Intake cam solenoid | A05 | Cam Control output |
| Exhaust cam solenoid | A06 | Cam Control output |
Engine sensors
| Function | Pin(s) | Notes |
|---|---|---|
| Coolant temperature | A45 | |
| Intake air temperature | A25 | |
| Manifold pressure | A38 | |
| Boost pressure sensor | B44 | |
| Oil temperature | A13 | Turbo models only |
| Oil pressure switch | A26 | On/off switch, not a pressure sensor |
| Knock sensor 1 / 2 | A29 / A39 | |
| Narrowband O2, pre-cat | A17 | Heater output on A19 |
| Narrowband O2, post-cat | A37 | Not used, and neither is its heater on A09 |
| A/C pressure | B15 |
The factory narrowband on A17 is fine for watching cruise, but you cannot tune boost on it. Fit a wideband controller and read lambda over CAN.
Drive by wire
| Function | Pin(s) | Notes |
|---|---|---|
| Throttle motor + / - | A27 / A28 | |
| Throttle position 1 / 2 | A44 / A16 | Two tracks the ECU cross-checks |
| Pedal position 1 / 2 | B17 / B18 |
Driver and chassis inputs
| Function | Pin(s) | Notes |
|---|---|---|
| Park/neutral switch | A02 | |
| Clutch switch | B04 | Manual only |
| Brake switch 1 / 2 | B25 / B32 | |
| Reverse switch | B30 | |
| Power steering switch | B31 | |
| Cruise control | B16 |
Outputs
| Function | Pin(s) | Notes |
|---|---|---|
| Fuel pump | B27 | |
| Thermofan 1 / 2 | B24 / B35 | |
| Boost control solenoid | B19 | Turbo models only |
| Dual intake runner | B03 | Non-turbo only |
| A/C control | B02 | |
| Alternator control / monitor | B28 / B29 | |
| Starter relay | B05 | |
| Engine control relay | B37 | |
| Evap (emissions) purge | B22 | |
| Vehicle speed output | B36 | |
| Reverse lockout | B42 |
Power, grounds, sensor supplies and CAN
| Function | Pin(s) | Notes |
|---|---|---|
| Permanent 12 V (battery) | B40 | Always live |
| Switched 12 V (ignition) | B09 | Wakes the ECU |
| ECU main power (13.8 V) | B34, B46 | |
| Battery negative | B01, B10, B11, B12, B23 | Main power grounds |
| Sensor 5 V supply | A21, A36, B08, B20, B45 | |
| Sensor ground | A22, A32, A40, A43, B21, B33 | Keep these separate from power grounds |
| CAN high / low | B13 / B14 | Vehicle CAN |
Pins not listed here (A01, A10, A11, A18, A20, A42 and B06, B07, B26, B38, B39, B41, B43) are empty in the Haltech pinout.
Diagnosing with this pinout
- Confirm power first. With the key on, you should see battery voltage on B40, B09, plus the 13.8 V ECU power pins B34 and B46.
- Check the 5 V supply at any of the supply pins. If it is low, a shorted sensor somewhere is pulling it down. Unplug sensors one at a time until it recovers.
- Back-probe the input you suspect while watching the matching channel in ESP. If the voltage changes at the pin but not in software, look at the input setup. If it does not change at the pin, look at the wiring.
Before first start, work through initial ECU setup and plug-in model selection. If your FG Mk I radio needs attention after the swap, the radio reprogramming guide and reprogramming cable cover it.
FAQ
Why does the post-cat O2 have a pin if it is not used?
The pin exists in the factory connector. The Haltech simply does not use the rear sensor for fueling.
Can I repurpose unused pins?
Often, yes, but it depends on what the ECU has behind that pin. Ask us before you add wires to the plug.
