(AEM EMS) Add a Fluid Temperature or Pressure Sensor

These instructions detail adding fluid temperature or fluid pressure sensors to an AEM EMS for displaying on gaugeART. Installation will vary for other ECUs. Please consult your user manual for details. These sensors are available from gaugeART – (pressure sensors & temperature sensors)

You should first determine how you will physically install the temperature or pressure sensor. Often, adapters are available in the aftermarket to easily connect these sensors to your engine. You should check with a part supplier who specializes in your vehicle if you need help.

  • Vw-ecu-terminal-instrument-plug-pin-terminal-vw-small-refit-terminal.jpg_350x350Adding sensors to the ECU requires you to wire the sensor in to the vehicle’s ECU electrical harness (where it plugs in to the AEM EMS) using the spare electrical terminals provided with the ECU. Terminal kits are available from AEM if you no longer have them. Installing the terminals to the wires requires specialty wire terminal crimpers.
    NOTE: proper terminal crimping is critical. ECU terminals require special crimping tools for open barrel terminals. Inexpensive open barrel crimping tools can be purchased online (example: IWISS SN-28B).
  • The AEM EMS has configurable jumpers internally to change between 0-5V, EGT, and thermistor sensors. Adding thermistor fluid temperature sensors for an input such as oil temperature requires opening the ECU and changing jumpers. Opening your EMS enclosure may void your warranty. The components in the ECU are delicate. If you are not knowledgeable about or are uncomfortable with the following steps, we recommend contacting AEM to make the change for you – which they will do for a nominal fee.

oil / fuel pressure sensor: AEM part number 30-2130-100 or 20-2130-150

These sensors have three wires: +5V reference, sensor ground, and sensor output. All three wires will be wired to the ECU.

  • sensor ground: wire to available sensor ground (if none are available, you may need to tap an existing one)
  • +5V reference: wire to available +5V reference (if none are available, you may need to tap an existing one)
  • signal: wire to available 0-5V input (see “EMS 0-5V and Therm Input Configuration” below


Once wired, the pressure sensor will be added to the telemetry setup (click here for details for: serial gaugeART or CAN gaugeART). When adding a pressure sensor to the telemetry setup, select the actual ADCR number from the list (ie. ADCR 16). If the gaugeART gauge is a digital type, choose the correct input type under the “digital” tab as shown (choose either “AEM PSI 0-100” or “AEM PSI 0-150” depending on what sensor your have. If the gaugeART gauge is a circular or bar type, the gauge is linear from 0-100 PSI or 0-150 PSI.

oil temperature sensor: AEM part number 30-2012

These sensors have two wires and produce a variable resistance based on temperature. The polarity of these sensors does not matter (either of the sensor’s two terminals can be wired either way).

  • terminal 1: wire to available sensor ground (if none are available, you may need to tap an existing one)
  • terminal 2: wire to available EGT 1, EGT 2, EGT 3, or EGT 4

EMS 0-5V and Therm Input Configuration

Pressure sensors use available “0-5V” inputs. Pressure sensors may also use “EGT” inputs however this requires the ECU to be opened to configure the jumpers to “0-5V”.  Temperature sensors use available “EGT” inputs and require that the ECU to be opened to configure jumpers to “Therm”.

Check with your ECU’s installation manual to locate an available 0-5V input (also named ADCR input). These are typically listed in the AEM manual as “Spare 0-5V Channel”. ADCR channels may be listed in the manual only by their name and not ADCR number. Commonly available ADCR numbers and channel names are listed below:

ADCR 3 = MAF 0-5V input
ADCR 10 = Lambda #2 0-5V input
ADCR 11 = PR Press 0-5V input
ADCR 12 = Baro Sensor 0-5V input
ADCR 13 = Gear 0-5V input
ADCR 14 = Ftemp 0-5V input
ADCR 15 = EGT 4
ADCR 16 = EGT 3
ADCR 17 = EGT 1
ADCR 18 = EGT 2

To use EGT inputs, you must open the ECU to set the jumpers. 

The ECU’s input jumper will now need to be set to the correct sensor type. Remove the 8 screws as shown using a No. 1 Phillips screwdriver.

Remove the four screws as shown. Be careful to not lose the plastic bushings between the two boards and the aluminum nuts that the screws thread in to.

While making sure your body is properly grounded to prevent static discharge, slowly rock the top and bottom circuit boards apart (making sure to not bend the pins out of shape). After rocking the boards several times apply upward force and the top board will begin to loosen. As it begins to loosen, carefully pry up on the side of the top board that connects to the bottom board.
Locate the block of four EGT jumpers (labeled JPEGT1, 2, 3, and 4 (AEM 30-6050 board shown for example with EGT 1 highlighted in yellow). Lift up on the jumper to reconfigure it from 0-5V (as shown in photo) and insert it between the pairs of middle pins as noted in the diagram labeled “THERM”.

Reassemble the two circuit boards together by inserting the top board in to the bottom and pressing down on the top board evenly. Install the plastic bushings, aluminum nuts, and screws. When seated properly, the two boards will bottom out on the plastic bushings. Slide the assembly back in to the enclosure and thread in the bottom screws first, then side plate and side screws.

Once wired, the temperature sensor will be added to the telemetry setup (click here for details for: serial gaugeART or CAN gaugeART). When adding a temperature sensor to the telemetry setup, use the ADCR associated with the EGT input you selected:

ADCR17 (EGT 1 Raw)
ADCR18 (EGT 2 Raw)
ADCR16 (EGT 3 Raw)
ADCR15 (EGT 4 Raw)

tempOnce telemetry is configured, you can add the temperature sensor to your gaugeART design. If a digital gauge is used, select the correct input type under the “DIGITAL” tab as shown as “AEM Temp F” for Fahrenheit or “AEM Temp C” for Celsius. Note that temperature sensors are not linear, so if you are adding marks in your design to indicate degrees, check the instruction sheet included with the sensor for approximate positioning.