I have a strange problem with my the gauge cluster of my 7th gen 1999 Toyota Celica. After changing the car battery, the gauge cluster (dials and odometer) will only light up if I connect the battery and turn the ignition whilst a door is open. However, if I close all doors and leave the car turned off for exactly one minute or if I connect the battery when all doors are closed, the gauge cluster does not work at all. Everything else electrical seems to work just fine in all cases. Any thoughts on what the root cause could be? Thanks in advance for any help.
Okay the root cause is old age. My Celica does the same thing and I just leave it alone. You would have to trace through the entire wiring system to see where the short is, but from my experience it's usually the dash unit itself is breaking down. The circuit board plastic is coming apart and all the solder joints start to come apart and then all kinds of weird stuff happens. But if you want a wild guess sometimes if you reground the dash unit with new ground wires, it may go back to normal
@scottykilmer Unfortunately it cannot be left alone. The dials and the odometer do not work under the typical circumstances that one starts the car with all doors closed. One possibility that I see is that something indeed shorted in the electronics of the cluster unit when I last changed the battery. However, the fact that the issue is reproduced exactly one minute after leaving the car turned off with all doors closed, leads me to think that there may be something to do with a relay.
@paulseph I like your idea about it possibly being a relay. You can try swapping the Power Main Relay with the Defogger Relay or Taillight Light Relay and see if that helps. https://charm.li/Toyota/1999/Celica%20ST%20Coupe%20L4-2164cc%202.2L%20DOHC%20%285S-FE%29%20MFI/Repair%20and%20Diagnosis/Diagrams/Electrical%20Diagrams/Fuse%2C%20Relay%20and%20Junction%20Box%20Data/Instrument%20Panel%20J%2FB/ I'm guessing you have a Celica ST Coupe.
@scottykilmer No, it is a 7-gen Celica ZZT231 (with VVTLi).
Does the gauge cluster work if the drivers side door is shut and the passenger side door is open? I'm wondering if maybe the wires that flex inside the drivers side door jamb every time the car door is opened and closed are worn out.
@oskool The gauge cluster works when only the passenger side door or only the luggage boot are open. So it does not look to be an issue specifically tied with the driver's side door.
You'll have to study the schematics. You can find some on charm.li
