common fuel sender data
| Vehicle | R_full (Ω) | R_empty (Ω) | Volts Full (1kΩ Pull-up) | Volts Empty (1kΩ Pull-up) | # of Senders |
|---|---|---|---|---|---|
| Audi S4 (2000–2020) | 56 | 285 | 0.27V | 1.11V | 2 |
| BMW 335i (2006–2013) | 410 | 60 | 1.45V | 0.28V | 2 |
| Chevrolet Camaro (1999–2020) | 33 | 240 | 0.16V | 0.97V | 1 |
| Dodge Charger (2006–2020) | 50 | 190 | 0.24V | 0.80V | 2 |
| Ford Mustang (2005–2020) | 15 | 160 | 0.07V | 0.69V | 2 |
| Honda Civic (1992–2020) | 5 | 110 | 0.02V | 0.50V | 1 |
| Infiniti G35 (2003–2008) | 3 | 80 | 0.01V | 0.37V | 2 |
| Lexus IS300 (1998–2005) | 4 (2+2) | 110 (55+55) | 0.02V | 0.50V | 2 |
| Mazda Miata (1989–2020) | 3 | 110 | 0.01V | 0.50V | 1 |
| Mitsubishi Evo 8/9/10 (2003–2015) | 8 (4+4) | 220 (110+110) | 0.04V | 0.90V | 2 |
| Nissan 350Z/370Z (2003–2020) | 6 (3+3) | 160 (80+80) | 0.03V | 0.69V | 2 |
| Subaru WRX (2002–2020) | 13 | 120 | 0.06V | 0.54V | 2 |
| Toyota FR-S (2013–2016) | 9 | 171 | 0.04V | 0.73V | 1 |
| VW GTI (2006–2020) | 350 | 50 | 1.30V | 0.24V | 1 |
About: These senders are simple resistance-style that are basically an arm or float that moves up and down with the fuel level.
Wiring: They will all be 2 wire senders, and sometimes there are two that are connected in series. You'll need to consult your manufacturer's repair manual or wire diagram to mimic or tap into the factory wiring.
Pull-up resistor: You'll need to wire a pull-up resistor in to receive a a good signal from the fuel sender unless you have a software-selectable pull-up you can select it in your tuning software.
Voltages: The voltages on the adjacent chart should be verified, but they're likely correct.
fuel sender configuration
Enabling: In Haltech NSP you'll need to enable the "fuel level" option under the "sensors" menu. Then input values from the chart above as a starting point.
Manual configuration: Make a note of your fuel sender voltage when you have an empty tank(or nearly empty), the easy way to do this is to use a fuel can to put in 5 or 6 liters from a completely empty tank, then note the voltage with the number of liters. Enter that voltage into the calibration chart in the adjacent picture. Drive to fill up your tank, then make a note of your voltage at a full tank. Input those values.
Gauge control output: Unfortunately you'll need to get creative with this one. If you have a CAN controlled fuel gauge you won't be able to control this with your Haltech. If you don't have a CAN controlled fuel gauge, you'll need to find the fuel input wire on your gauge cluster, create a generic output in your haltech settings, make the signal type "frequency", then start with "50%" for duty cycle, and make a "table" output mode. Experiment with different numbers in the table for empty "1/4 tank", "1/2 tank", etc.
Fuel level warning light
Functions: In the case of a low fuel level, if you have an available generic output on a Haltech ECU, you can wire to the negative side of a bulb in your cluster. If your bulb is wired internally (most are) you can buy a pigtail like in the adjacent picture. The pigtail holds a T5 bulb (for my IS300 gauge cluster). A set of 4 was less than $10 on eBay.
Wiring: Wire the Haltech output wire to the ground side of the bulb, and wire the other wire to a fused ignition switched positive source.
Configuration: Follow the settings in the adjacent picture in order to trigger the fuel light bulb on. This creates a generic condition that will enable your fuel warning light when the fuel level reaches 9L or less.
Use a CEL/DTC as a fuel level warning
About: As far as I know this can only be done in a Haltech ECU since they're the only ECUs that I know of with built-in OBD2 DTCs. This will trigger a check engine light if your fuel level drops below a certain voltage on your sensor.
Configuration: Set your diagnostic settings what is shown in the adjacent picture.
Requirements: Obviously this requires your check-engine-light to be operational on your gauge cluster and wired to your Haltech ECU in order for this to function properly.
Things to consider: If your sensor voltage rises as the fuel level drops(like mine), you'll need to set the "Raw Max" value to be bemeath your max voltage. If your sensor voltage drops as your fuel drops you'll need to set your "Raw min" value to be above the minimum voltage in your configuration.
