Lexus LS 400 - Recent Questions, Troubleshooting & Support - Page 4

1990 Lexus LS400 Service Repair Manual Download Try it asap.. I bought today. it's very cheap and very reliable. today they have offers as well.

probably worth checking code to get better ideas for diag

Check the main fuse under the hood .It is possible corroded

I would try a crank sensor

You just go to the link I attached I'm sure you will get the solution of your problem 1991 LS400

Sounds like some kind of short or loose connection in the instrument cluster. A few years ago I had a van that would intermittently decide to not crank when the key was turned even though everything else worked. I went online to a forum for that brand and model vehicle and did some searching for a no crank condition and found others who had experienced the exact same thing and described what was going on and how to repair it. I followed those instructions and found exactly what they described, performed the repairs which was the resoldering of some cracked solder joints where the wiring harness connected to the instrument cluster, reinstalled the cluster and never had another moments trouble. That was on a 1998 so your 1991 could be experiencing a similar problem. But instead if just taking things apart and trying to find the problem, go to a Lexus forum and do a search for something like "temp guage maxes out when key turned on and starter stops working but then starts but reads 10 MPH too high after tapping on top of dash". You might have to try different wordings to find whay you want but I'll bet you dollars to doughnuts somebody else out there has had the same problem and talked about it on the forum. You can even just Google your question but you'll get answers for all kinds of vehicles and not even remotely similar problems. Good Luck.

Sounds like you need to change your ignition switch. This happen when there are too many objects on your key chain.

It is not the fuse. Do It Yourself Diagnosis and Repair

More then likely your vehicle has a parasitic drain on the battery . A control module may not be powering down or something is on in the vehicle. Testing the electrical system like in this video is the way to find out . The BEST Way TO Perform Parasitic Draw Test

Always go directly to the ground and check it is clean and well connected. I speak mainly here of the body grounds. Battery to starter is fine cause it cranks well and headlights are operable, it's just the battery ground to the body that's giving you trouble. When electrical problems arise, Always go directly to the grounds first.

No, it makes no sense. You have V-8, right? Removing the exhaust manifolds will not provide any help in accessing the starter. The starter is in the middle of the engine.

Believe it is fuse no. 17 but go to bing.com and type in 1997 lexus Ls400 fuse panel. There are many diagrams there and you should be familiar with what your panel looks like.

Be sure you check engine oil level often. The low oil sensor will disable the ignition. If you turn A/C on the cooling fan should run continuous, Check the fan relays. Make sure coolant level is correct at recovery bottle, never open radiator cap. A scald hazard exist, be careful. This car is old and complicated, and is beyond your skill level to repair. Try to inquire here for advice, whenever possible. Don't throw good money at bad money