Hello everyone I bought a 1998 gs400 and when I got the car everything was fine but recently I started to have an issue where the car starts but nothing else works on the car I mean nothing other then the horn and hazard lights. The dashboard doesn’t come on, windows don’t go up or down, car don’t lock, seats don’t move, if I press on throttle car revs but it’s delayed. I checked all my fuses and wiring they are good. I’m thinking maybe my bcm. I found what each bcm controls since ik it has 2 and everything that doesn’t work either one controls certain things so I’m not 100% sure. I don’t know if anyone else has this issue before car also has remote start just to put it out there doubt it has to do with anything but just in case.

 

Sounds like a bad ground or corrosion somewhere, or a blown fuse you missed. Start at the battery and look for signs of corrosion. If you see bad connections at the terminals that are damaged or loose replace the cable ends, and if the cables themselves are full of that white/greenish acid, replace them too or try to cut off the bad parts if there is enough length to still reach the terminals. There are grounds from the battery to chassis and to the engine to check too. You may have a blown cartridge style fuse, some people find them hard to check. You have to pry the clear cover off them and use a test light to check for power across them.

 

There is 3 fuse boxes, are you certain you checked all the fuses with a test light to confirm everything is powered correctly? Have you done a good shake test of everything to see if you can find a short? Try giving a little knock on the ignition cylinder while it’s turned on but nothing is working, maybe the wiring to the ignition is faulty and shorting or something? If you can find anything that will get it to work even if just briefly it can yep narrow down the culprit.