club lexus folk--

hi, just starting down the path of upgrading our 2004 gx470, lots to learn but this is as good an issue as any to start with... our gx470 KDSS light has come on and off intermittently for years now. the local dealer was initially stymied - didn't even know what KDSS was! - but eventually gave us a story about how the road salt eroded a protective plate and compromised the unit. it seems to come on when it's hit with moisture or a big bump, and we're not sure if it's affecting driving performance or not. now just recently we also have dash lights VSC TRAC and VSC OFF popping up.

looking online it appears there are some simple wire jumping / reset procedures to get the VSC TRAC and VSC OFF lights to turn off, but i'd be curious to know what might have triggered these lights to come on in the first place, thoughts?

also curious if anyone has thoughts on how to address the intermittent KDSS light, how this might be affecting the car's handling, and what a good long-term solution/repair would be for this. we do plan on looking into possible suspension upgrades / air-bag deletes for the gx470, so i'm also open to bypass solutions for the KDSS issue if that would be consistent with doing a suspension upgrade / airbag delete.

thanks in advance for any insights/suggestions/pointers you can offer!

--josh (lakewood, co)

ps: worth mentioning i am mechanically inclined and have experience working on our other cars, just haven't started digging into the gx470 yet, so i'm open to techie solutions...

 

If you want to deal with the GX yourself, suggest to get a good scanner or Techstream program on a computer. I don't have KDSS. So I am not familiar that part. For the VSC TRAC and VSC OFF, could be as simple as gas cap. Get a code read first.

 

KDSS repairs are expensive, so be prepared for that. You can poke your head underneath and see if the bellows on the actuators at one end of both front and rear swaybars are wet with oil as that's a common failure point, but it sounds like the dealership was talking about corrosion damage to the valve block, located about mid-way down the truck on the driver's side frame rail.

The VSC TRAC and VSC OFF dash lights could be something as simple as a bad or not properly tightened gas cap.

 

these are great pointers, and happily give me an excuse to spend a little $$ on a code reader which i've been wanting to do for awhile now! still not sure why a gas cap would trigger a stability control dash light but i do understand that these lights typically underinform and that a code reader is the way to go. also i believe ianb2 is correct that our dealer was talking about a corroded valve block, and yes/uggh, this looks to be pretty pricey if i have them do the work.

thanks for the great info, much appreciated, i'm excited to start digging into this car, we sure do get some great use out of it!

 

I had found a great video on youtube a few months back where a guy built his own KDSS service tool, and showed how to use it, but sadly that video has since been taken down.

 

Apologies for the delay in updating but it took us this long to make a decision on the GX470. We ended up having a local Lexus specialty shop in the Denver area do the air bag delete and an Eibach coilover lift. Everything went well and the suspension performance is greatly improved, especially on the last seven miles of washboard forest road we drive every day. The VSC TRAC and VSC OFF lights are gone. There don't appear to be any sway issues, either at slower off-road speeds or at highway speeds.

The one remaining issue is that the KDSS light is still on. We know our KDSS unit is bad, likely due to corrosion, the shop says they can normally disable the KDSS after this conversion but because the unit is bad they can't, and they don't seem real concerned about it and we're not seeing any odd behavior in terms of sway, but it does make me wonder if anyone can chime in on if the KDSS light being on / the KDSS unit being bad but still in this system is going to cause any other issues than an annoying dash light?

(update crossposted to this thread also: https://www.clublexus.com/forums/gx-...dss-model.html)