No EIC display but engine runs fine..need help diagnosing EIC issue.

[Dudge]

My ls140 has been parked for a while..I went out to charge it today to get it up and running. I noticed that the ignition key slot was about halfway between off and position one but thought nothing of it (it's always been slack) However once the battery was charged I get a constant high pitched warning sound when I turn it on... The eic doesn't come on and I can't hear the preheat ritual. That said she started third turn and is running fine...boom working etc but the eic is not lit and the high pitched warning noise continues. Obviously I don't want to use it in this state as I can't monitor the systems. I have eyeballed all the fuses and checked them with a multimeter just to be sure.

When I bought it the seat switch and parking brake had been bypassed..( no judgement please it is what it is) . But I have had it and used it fault free for over 4 years.. any ideas on what is going on? I don't have lights either...

Any help diagnosing the issue would be great...going to take a look at the ignition switch next. ..

Thanks in advance.

 

[Dudge]

Just an update…still need help…lights are working….engine fires up and runs with no issues..boom, bucket all working as they should. When I turn the ignition on the warning beep sounds, normally this stops when the heater cycle has run, but it is staying on all the time. If I push and hold the Book symbol there is a second sound from the board that stops…hard to describe but a sort of muffled low buzz… have visually inspected the board but can't see any obvious issues..caps all look good…no obvious burnt or damaged traces.

Can anyone let me know which terminals on the input wiring I need to test to see if there is power going to the board and what voltage I should expect to see… thanks again