Engine ECU
Engine ECU
The ECU (Electronic Control Unit) for the UZZ32 is very similar (but not identical) to that from the UZZ31 Soarer.
The engine will not run without an ECU, and if the ECU is bad it may not run properly. Capacitors in the ECU deteriate over time but can be replaced as long as the leaking chemicals have not caused irrepairable damage to the circuit boards.
ECU location
The ECU is located on the passenger side floor.
ECU Removal
To access it, remove the carpet. Be aware that the carpet has both a firm foam backing (which will tend to break if the carpet is folded) as well as various integrated pieces of hard plast used to assist in mounting. This means that the carpet will not fold easily, and/or that if it does fold, the softer carpet material may tear. In addition, the plastic pieces at the back of the carpet may scratch you and/or the other pieces of the trim.
The ECU is also covered by a black plastic "shield", which is held in place by two nuts.
There is a clip-on cover that provides further protection to the cables.
There are 3 x 40-pin cable harnesses entering the ECU.
- The right-hand side one "just" pulls out. if necessarym carefully lever it out by carefully using eg a flat head screwdriver rather than pulling on the cables, but be aware that the old plastic is likely to be brittle.
- The other two plugs require the undoing of a bolt (which is likely hidden from view under the cables). This is easier to get to once the ECU has been tilted upwards.
There are two screws on the side of the ECU that secure it to the mounting bracket, but it is easier to remove the bracket AND ECU, and then separate the ECU if necessary.
The ECU is (?) held in place by two further nuts as well as a "fold" in the metal that hooks into a corresponding bracket. Lift the rear of the ECU (the side facing you) up about 30 degrees so that it unhooks from the part that is further forward in the footwell.
ECU repair
ECUs can, depending on the amount of damage, be repaired.
ECU wiring
As seen in diagram 1 and diagram 2 the Engine ECU is connected to:
- Engine control items such as
- Fuel injectors (x8)
- IAC Valve
- Air Flow Meter
- Throttle Position Sensor
- etc
- etc
- Dash
- Cruise Control
- Traction Control
- Automatic Transmission (solenoids x 4, PRND switches and indicator light, mode switch and light)
- Stop light switch
- Malfunction Light
- Diagnostic Connectors (x 2)
- Oxygen sensors (x 2)
- Suspension Controller (not shown in diagram, which is from a uzz30/31, not a UZZ32)
- Aircon controller
- Park/Neutral switch
- Fuel pressure ?
- Speed sensor
3rd party ECUs
3rd party ECUs are available but historically quite expensive.