that sounds not good
In '98 the central electronic type used in the JE changed with only one big
!!! Problems with ABS, main instrument, lights, radio and so on... !!!
As you wrote the problem is still there for 5 to 10 minutes after starting the
Mostly the main electronic element behind the instruments is broken (cold
and warm periods directly behind the front screen) and if the temparature
will grow up all functions might be okay.
If you know a good specialist he will find the broken area on the electric board.
Worst case: You have to buy a new central electronic including the main
Regards from Germany