Ls400 Mk4 Dashboard Fault

Ian R · December 1, 2014

Hi,

My LS has developed an intermittant dashboard fault. The engine temp gauge drops to minimum, the gear indicator goes out, the average mpg figure at the bottom goes to 0.0 and the outside temp reads - -. The fuel gauge, speedo and tacho all remain working. This lasts for a few seconds and then everything returns to normal.

I have read about dash faults on Mk2s. Does a similar thing happen to Mk4s? Does anyone have a clue as to what links all these readings? The odd one for me is the outside temp because that is in a seperate area, or is it linked to the dash?

Thanks

Ian

n4chv · December 1, 2014

This used to happen on my Mk IV LS400 - it was an intermittent fault as well and typical for me, when both a Lexus dealer and my local garage had a look it was working fine.

Thankfully, given how good the rest of the car is it wasn't something that bothered me too much but I was never able to get a diagnosis on why it happened

It's not a serious issue but it can be slightly annoying.

I'd be more concerned if the fuel gauge needle dropped to the bottom !

Spottedlaurel · December 4, 2014

Is this linked to the ignition switch fault that was mentioned on another post recently?

Ian R · December 5, 2014

Mine is just a couple of gauges and a light, not a big scale shut down. I will put a voltmeter in the car and see if the gauges failing is related to the alternator stopping \ reducing charging. I would have thought this would have prompted a warning light or message though.

harrylime · December 5, 2014

It may be unrelated but I have starting issues with mine and strange behaviour with vsc lights etc. the consensus on here seems to be that the LS is very sensitive to voltage drops / Battery condition. As it has just turned a fair bit colder where we are, no doubt the Battery is suffering a bit