hi there,
there are 2 pages on this site that may help you out regarding the wiring off the ecu.
On
http://www.lextreme.com/1uzfe_variants.html, it states the following
There are 6 variants of the engine. Crown (pre-96), Crown (post-96), SC400 (or Soarer for JDM versions), SC400 “active” or UZZ32, LS400 and Celsior
ECU:
Crown UZS131 - has two modules the ECU runs the engine and the ECT runs the transmission. The ECU is happy to run without the ECT Crown UZS 141 & UZS151 – has single ECU/ECT and can be hard to run without the transmission or external sensors. SC400 - uses single ECU/ECT. LS400 - uses single ECU/ECT. Celsior - uses single ECU/ECT.
Whilst the Crown UZS 141, UZS151, SC400, LS400 & Celsior use a combined ECU/ECT they are not interchangeable.
Wiring Harness:
Crown UZS131 - does not have provision for oil level gauge. Crown UZS 141 & UZS151 –Oil gauge in alloy intermediate plate below alternator SC400 - some models do not have Trac so a different loom SC400 - Active is unique and won’t interchange to another engine. LS400 – same as Celsior. Celsior – Same as LS400
Whilst you can interchange the harness between different engines some differences do occur. Oil level gauge sender on LS400 and Celsior models are on the right hand side at the front (behind the power steering pump)whilst the gauge sender on SC400’s is in the centre of the engine on the left hand side (behind the air conditioning
On
http://www.lextreme.com/splitsec.html, it explains the following.
U.S. Spec Lexus LS400 and SC400 ECU is located on the driver side under the glove compartment. Once you open up the panels, you can not miss it. The LS400 using T8-a diagram and SC400 uses T7-a. The below connector diagrams are view as if you are looking at it directly. Here is a wiring diagram for the LS400 Wiring Diagram (1) and LS400 Wiring Diagram (2) Here are the SC400 ECU diagrams 92-95 SC ECU Diagram (1) 92-95 SC ECU Diagram (2).
So you may need to work out correctly is the following,
what engine do you have?
what type of plug is connected to the ecu?
If you have a JDM engine with a T7a, then you need to wire up as a soarer.
hope this helps you out