Technical Key code error

[wiltshire]

Key code error.
Petrol bug, 2000 model
The battery was removed to charge it, it was replaced and the car wouldn't start. Key code error and the key not giving bleep and flash when locking/unlocking.
Finally called RAC who tinkered with a laptop, said engine management part of the ecu wasn't powered. He took out all manner of relays and fuses and reseated them but I think the thing that cured it was a spray of contact cleaner on a wide data cable (?) connector from down behind and to the left of the battery somewhere.
The feeling of relief when the warning light went out and the engine fired up.

Things were a lot easier in the old Strada days and the 2300 years before that

 

[jackwhoo]

Well done RAC for persevering and getting to the bottom of it.
There is a fuse for code system lurking around the battery somewhere.

 

[wiltshire]

Getting a bit closer to the answer, I put on a different battery and the code error was back again. After some ocean going, industrial grade, swearing I went through the routine of checking the fuse/relay box and the data connector gizmo. Pressed all of the relays and fuses back in.
A start was attempted, more in hope than expectation, and the code light went out and the engine burst into life.
My theory is that hefting the battery in and out of the enclosed space means that your forearm pushes on the flexible box and the stuff inside becomes loose.

 

[wiltshire]

Getting a bit closer to the answer, I put on a different battery and the code error was back again. After some ocean going, industrial grade, swearing I went through the routine of checking the fuse/relay box and the data connector gizmo. Pressed all of the relays and fuses back in.
A start was attempted, more in hope than expectation, and the code light went out and the engine burst into life.
My theory is that hefting the battery in and out of the enclosed space means that your forearm pushes on the flexible box and the stuff inside becomes loose.

I had a very dead battery and took it out to inspect/recharge. I was expecting the code error at the battery had been out for two days. Have just put battery back, I made sure all relays are seated in the box by the battery and it started first time. No code error, so I'm now fairly sure that you don't lose the code when taking the battery out.