Wtb: S13 tcu

[youngfab59]

Hey everyone. I?m looking for a functional S13 TCU. Please PM me if you have one available. Also if have pictures or videos of the TCU actually working that would be most appreciated. Thanks.

[Deja-vu Garage]

Messaged you.

[brndck]

how are people damaging these??? I've sold 4 TCUs in the last month, and in 20 yrs of owning a 240 have never had one go bad.

[mechanicalmoron]

how are people damaging these??? I've sold 4 TCUs in the last month, and in 20 yrs of owning a 240 have never had one go bad.

Wrote a reply to TCM, then remembered this stupid little thing.

Probably cutting a radio harness, or leaving bare wires when faced with unused functions during a radio install. Or mixing wires up, or testing them recklessly. I forget which one (light control?) but there's a wire in there that will burn a printed trace in your TCU if it shorts (to ground, I think).

It can be mostly repaired with a soldered jumper. The dimmer might not work after, though.

[youngfab59]

how are people damaging these??? I've sold 4 TCUs in the last month, and in 20 yrs of owning a 240 have never had one go bad.

Wrote a reply to TCM, then remembered this stupid little thing.

Probably cutting a radio harness, or leaving bare wires when faced with unused functions during a radio install. Or mixing wires up, or testing them recklessly. I forget which one (light control?) but there's a wire in there that will burn a printed trace in your TCU if it shorts (to ground, I think).

It can be mostly repaired with a soldered jumper. The dimmer might not work after, though.

My TCU was already burned when I got my S13. It was probably due to a grounding issue when the PO installed the radio just as mechanicalmoron mentioned.

@Mechincalmoron how do you prevent the previously cut radio harness from damaging other TCUs?

[mechanicalmoron]

My TCU was already burned when I got my S13. It was probably due to a grounding issue when the PO installed the radio just as mechanicalmoron mentioned.

@Mechincalmoron how do you prevent the previously cut radio harness from damaging other TCUs?

Find the wire and isolate it - it comes through the stock radio plug, so it's almost certainly somewhere behind your radio - if you can't find anything cut at the radio harness, then I'd suggest checking diagrams and starting by testing at the tcu plug for a short to ground (continuity to ground on whichever wire it is, which should have none whatsoever, unless it's currently shorted or plugged into a radio)

https://www.nicoclub.com/archives/fix-for-240sx-instrument-paneldash-lights.html

I think the "ground it out" option is assuming you have a bad tcu, and will instantly fry a good one.

It also mentions there's a dimmer fuse, which could either blow instrument lights or just prevent dimming, depending on how it's wired.