Hello,

The CPU of my '91 convertible has been acting strange for a while, the alarm just quit and all the little buzzers and keyhole lights quit working, and earlier I noticed a burned smell.

I finally took apart the CPU and discovered there had been a fire: one of the resistors, marked R1, is completely burned and I can't even read off the resistance value for it.

Does anyone know what the resistance value should be for this component?

Also, I checked on replacing the CPU, or at least this particular circuit board, at the Mazdatrix site, but am confused as to which board I should pick since there are a couple of different choices, none of which seem to match. The one I need is the larger one, with the buzzer and alarm circuit on it, spanning the entire length of the CPU case.

Please help me figure out which one I need!
Would you recommend I try repairing the circuit board, or is it better just to replace the board/CPU?

Thanks a bunch!

 

probly cheaper to try and find a used ecu than to repair it. Just shell out the 1k for the haltech