Circuit Diagram For Instrument Cluster Urgently Needed

[BaxfromNZ]

My instrument cluster has gone dead.

Initially it was intermittent but now it is permanent.



This is the last model LS400 with variable valve timing prior to the LS430 so the instruments include a trip computer which my previous 1996 LS400 did not have.



Several kind people have sent me wiring diagrams but what I need is the
circuit diagram of the actual printed circuit boards inside the cluster
as the cluster is currently at an instrument repair shop and they have
hit a brick wall.



There is a main board and one or two daughter boards in the cluster one
of which is the power supply circuit board and this is where I suspect
the fault might be.



If you have access to a diagram or know where I can source one I would really appreciate it.

I have replaced all of the electrolytic capacitors on the main board myself but this did not fix the problem.

I appreciate that Toyota do not normally release this information because they would prefer to sell me a new one but there are some clever people amongst you who may have managed to wheedle one out of the strongroom somehow!

Read more: http://www.clublexus.com/forums/ls400/745617-1998-ls400-instrument-cluster-circuit-diagram-urgently-needed.html#ixzz34O7LGXgM

[steve2006]

I've never come across the actual cluster diagram,perhap be easier and cheaper to get hold of a working 2nd hand cluster.

[BaxfromNZ]

You can't find them second hand here in NZ otherwise that is exactly what I would do.

My only option then is to fix the one I have got.

[fred81]

those circuit diagrams were most likely never released. lexus probably won't even have them, as they aren't likely to be the manufacturer of the instrument cluster.

[Malc]

Don't know if this will help at all ....... Chris Vince ( on here ) fixed my Mk2 instrument panel, just popped it out and soldered whatever ............... he might be able to guide you.

Malc

[steve2006]

The only diagram of a specific Lexus unit I ever got a circuit diagram/manual for was the Pioneer 6 disc changer in the boot and that was from Pioneer not Lexus.

I assume your LS is RHD? If you are really stuck I could make enquiries about a replacement here in the UK and perhaps arrange something to pay and get it over to you in NZ.

[BaxfromNZ]

Fred81: Lexus will have them, they just will not readily release them because they would rather sell a new part but the age of the car is such that the likelihood of someone being prepared to pay a couple of thousand for a new part is fast diminishing as the value of the car drops.

Malc: Thanks for the suggestion I may follow that up but I suspect that whoever tries to fix it now is definitely going to need the PC board diagram as the experts over here have tried all of the obvious things (I hope!).

Steve 2006: You are right; if I knew who the instrument cluster manufacturer was I would go straight to them and I think I would have more chance of getting one that way. If I run out of options I may contact you about sourcing one over there - thank you for the offer.

Incidentally I suspect the engine manufacturer for these cars is Yamaha not Toyota and I wouldn't mind betting the the Yamaha V8 four stroke outboard motor probably looks remarkably like a Lexus V8 motor!