AFR Calibrator – Closed Loop Tuning
The MAPECU Dual Channel AFR Sensor Calibrator is specifically designed for the Bosch™ Air Fuel Ratio (AFR) Wideband Sensor to facilitate closed loop tuning. Suitable for MAPECU2 and MAPECU3 AFR Adjust function. MAPCAL2 V3.1 or later is required for a MAPECU2 to support the AFR Sensor Calibrator. All MAPECU3′ support this feature. The AFR Sensor is a four-wire sensor with unique wiring as per the diagram below.
The MAPECU AFR Calibrator has two channels designed to alter the AFR the OEM ECU “sees” from two AFR Sensors, e.g. left and right bank of a V6 engine. This AFR Adjust feature is driven by the 494 zone AFR Adjust table in the MAPECU2/3 allowing the user to alter the AFR’s the OEM ECU “sees” in closed-loop mode. Specifically designed for naturally aspirated to forced induction conversions where AFR’s richer than 14.7:1 are required at the onset of boost.
There are two normal heater connections (B+ and HA1A) but the signals form a “differential pair” where both signals (A1A+ and A1A-) are above Ground.
Note: Wiring diagram shown where Analog Output #1 is configured to the “AFR” function in MAPCAL. See MAPCAL2/3 Manual for configuration details.
Warning: Do not connect the Dual Channel AFR Sensor Calibrator to +12V, it must be connected to the MAPECU2 +5V output.