Toyota 4afe | Ecu Pinout

Check injector resistance. Unplug an injector and measure between B02-B05 and ground. Standard resistance: 13.8Ω. Shorts to ground mean a blown injector driver inside the ECU.

These pins are primarily found on Toyota part numbers such as (common in early 1990s applications) as well as MA-5840 and MA-5498 models.

A "dead spot" in the throttle position sensor signal will cause hesitations during acceleration. Safety and Best Practices toyota 4afe ecu pinout

| Pin # | Description | | --- | --- | | 16 | Idle Air Control (IAC) Valve | | 17 | Fuel Pump Control (FPC) | | 18 | A/C Compressor Control (A/C) | | 19 | Fan Control (FC) |

If you are dealing with a non-starting, misfiring, or high-idle 4A-FE, checking these pins is your first step: Check injector resistance

BATT must have fused, constant 12V power to retain ECU memory. +B and +B1 need 12V power triggered by your ignition switch through an EFI relay. E1 must be grounded securely to the engine block or chassis.

On OBD-I 4A-FE systems, locate the "Diagnostic" box under the hood. Use a paperclip to jumper pins TE1 and E1 . Turn the ignition key to ON. Count the flashes of the Check Engine Light on the dashboard to read manual fault codes. Shorts to ground mean a blown injector driver inside the ECU

Depending on your vehicle's model year, the 4A-FE utilizes distinct physical ECU plugs.