One time, pause, then 2 times, three times, pause.so on for each mode, 1 through 5. The red and green LED's on top of the ECU will blink simultaneously. Using a small screwdriver or tool, move it to the diagnostics position. A small toggle switch is behind it with 2 positions, "ON" and "DIAGNOSTICS". For VG30i: There is a little plastic tab you pull off of the side of the ECU(facing the door). Light is flashing and the ECU will keep all stored codes and the check engine light will remain on.Ģ. To keep the codes stored, simply turn the key off as the check engine
Wait 5 seconds, then turn the screw fully counter clockwise.ĥ. To clear all stored codes and turn the check engine light off, turn the screw fully clockwise while it is in diagnostic mode. (number of long flashes is the 1st digit, number of short flashes is the 2nd digit)Ĥ.
The check engine light will then begin to flash the trouble code. Wait 5 seconds, then turn the screw fully counter clockwise.ģ. Turn the 'diagnostic mode selector' screw on the ECU fully clockwise. All of the lights in the dash should be on.Ģ. Turn the ignition switch on, but do not start the engine. This is where the LED lights are visible on top of the ECU.ġ. Remove that and the cover will pull off.ĭiagnostic selector switch with cover installedĭiagnostic selector switch with switch cover removed and set on top of the ECU. Seat removed ECU in place on the floor with cover. VG30E ECU's have a slotted round switch in the same place as the toggle switch.
Pictures: This is the ECU from my very dirty (and wrecked) 89 VG30i Pathfinder. In any case it will have one or the other. Some early 4-cyl HB ECU's have the switch as well. The 4-cylinder ECU and the VG30E ECU has a slotted switch that turns 1/4 or 1/2 turn clockwise and counterclockwise to do the same task. The VG30i ECU's have a tiny toggle switch on the side of the ECU with a small snap-in switch cover that must be utilized to select the diagnostic mode of the ECU. You can also remove the seat if you want, it makes access a little easier. You can gain access to it by simply sliding the seat all the way forward and removing the plastic cover from the ECU. The ECU is under your passenger's side seat.
How to pull ECU error codes for 87-95 Pathfinders and hardbody pickups: