AEM 30-6101 Series 2 Plug & Play EMS User Manual
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This product is legal in California for racing vehicles only and should never be used on public highways.
Fuel Pump Control
As supplied from Toyota, the OEM ECU interfaces with a fuel pump ECU to control the speed,
high or low, of the fuel pump based on load. The AEM EMS has the ability to replicate this
functionality; however it is configured in the Startup Calibration to run the fuel pump at high
speed at all times.
The EMS Output COIL8 (Pin 22A) is used to send a 5V signal instructing the OEM fuel pump
ECU to energize the fuel pump. Configuring User PW Out to use LS8 and, for example, User
PW Analog In to MAP Volts will allow the voltage sent to the fuel pump ECU to be varied in
relation to MAP Volts/pressure. Increasing the duty cycle of the LS8 output will decrease the
speed of the fuel pump.
WARNING: Reducing the voltage sent to the fuel pump can affect fuel pump output (volume
and/or pressure). If you wish to decrease pump speed, monitor fuel pressure and air-fuel ratio
very carefully to avoid engine damage!
WARNING: Do not use pin 22A to control a fuel pump relay directly, it must be connected to
the OEM fuel pump ECU only. If an aftermarket fuel pump relay will be installed, wire it to be
controlled using a spare low side output (for instance, LS9 is available on pin 68B). Be sure to
configure the output to use the Fuel Pump function using Tools>>Configure Outputs.
Peak and Hold Injector Drivers
Injectors 1-12 include Peak (4 amps) and Hold (1 amp) injector drivers. These drivers may be
used with peak and hold or saturated type injectors. The factory Toyota wiring harness for
some vehicles may contain a resistor pack to prevent excessive current when using low-
impedance injectors with the stock ECU. With the 30-6101 installed, users can elect to remove
and bypass the OEM resistor pack for more precise control of low-impedance injectors.
Please note that the injector response time will be different with and without the factory injector
resistor pack. If the OEM resistor pack has been removed and bypassed, please choose the
correct battery offset for your injectors using the Setup Wizard. Most battery offset wizard
configurations will specify