omidathari

Hi folks,
I bought a 1994 LS400 which I enjoy driving very much, and I was researching some common issues and preparing myself for some of the issues that may come up.
For example, I saw the ECU issues that require capacitors.
Question that came up for me are:
- Is there a transmission control module as well?
- Is there ignition control, fuel control modules etc that are also potentially problematic given the age of the car.
- What other modules or components are super critical and not available easily. I'd like to have a spare one of anythings that may be critical in case of a breakdown.
Thanks in advance

400fanboy

AFAIK there are no other electrical modules that have problems. Only the main ECU. There are other modules, like the body control module which controls doors and the remote key fob on newer cars, but that thing is virtually indestructible.

https://www.clublexus.com/forums/ls-...l#post10411641

timmy0tool

iTrader: (7)

the ECU controls everything related to the engine and trans, hence why it's the most likely culprit with odd behaviors. there is no TCU. there are body control computers that can fail as well but not as often as the ECU. i would source an ECU (get the same year ECU) as a spare so you can have it re-capped keeping the car operational while having a spare at the end.

what's also common that i have not heard recently is the wire harness on the trunk lid hinge that tends to get brittle due to constant open/close. the insulation breaks (inside the wire loom) where it bends into the trunk space and starts to short each other leading to no tail lights or other weird electrical gremlins.