Alhambra Electrical Problem

[dawsonprops]

Our Seat Alhambra 05 plate Diesel TDi lost all electrics. We replaced the battery and alternator and it was ok for 2 weeks. Then the alternator light started coming on again, and now it won't power any of the major electrical items such as heated seats, windscreens, etc the voltage on the meter in the car drops as soon as you switch anything on. Can anyone help?

[kenney]

For some reason the alternator is not charging properly,check the terminals on the alternator,to make sure the nuts are secure

[towcestervag]

did you replace the alternator pulley?

[dawsonprops]

I don't think the mechanic did. Would that make a difference? He is worried that the ECU has gone. Thank you for replying by the way.

[dawsonprops]

Hi Kennet, thanks for your reply. i didn't change it a local mechanic did. Much too cold and complicated for me to consider it, although as he says it does look quite accessible. He is worried that the ECU is playing up?

[towcestervag]

unlikely its ecu
check to see if youve got ignition feed at blue wire at back of alternator
check to see what voltage alternator is charging at large 13mm bolt terminal should be approx 14volts
check to see if any faults show up on diagnostic scan as you have a central electrics controller under dash

[dawsonprops]

Hi Kenney,

Apologies for the delayed reply and the mis-spelling of your name before! The mechanic changed the alternator again on xmas eve and it does appear to be working fine now. Obviously the recon alternator was playing up. Thank you very much for your help with this,

Rich