Ford KA 2004 1.3K

[AlexKA22]

My partner has a 2004 Ford KA that has been off the road since before covid. I’ve been through and fixed lots of issues it’s had, rusted fuel tank, replaced that, new pads and discs as the others were shot and massively rusted. Given it a full service. Other than that before it’s MOT again I thought everything was fine but we had given it a new battery as we thought the other one had just died due to being sat for a long period of time, whilst working on the car the new battery had depleted in charge but I thought this was just due to not being driven around and didn’t think to much into it.

Came to collect my car after MOT from Halfords to be told it had been Aborted due to an alternator defect, the receptionist also told me the wiring to the alternator had been ‘bodged’ but wouldn’t elaborate. I did ask to speak to the mechanic but was too busy apparently so that’s all I got. They quoted me £300 for a new alternator which I’m confident I can change myself for £120. Does anyone have any ideas what the issue may actually be? The receptionist said Halfords couldn’t touch the electrics but can change the alternator? Seems a bit odd. I’ve cleaned all the terminals, used a multimeter everywhere, the issue seems to arise when everything in the car is put on, heating, radio, lights etc.

Didn’t have this before hand, but the belt has started squeaking, least I thought it was the belt, replaced that and it is still making the same noise. Could it be a bearing in the alternator? 

Any help would be greatly appreciated.

[TomsFocus]

Halfords Autocentre are just fitters.  They can only fit new parts, they cannot make repairs to existing parts such as wiring or welding.

If the wiring has been bodged, it seems unlikely that a replacement alternator would help...but that's all they could charge you for.

If damp has got into the alternator while parked, it is possible to have damaged it.  We had the same thing happen on a relatives cars that was fine before a short period off road.

[isetta]

Have you looked at the alternator wiring?  Is it bodged?  Eg does it have a poor connection which cannot conduct enough power for the demand of lots of stuff on at once?  

[iantt]

Usually the wiring corrodes a short way from the alternator  connector  

[AlexKA22]

I've had a look at the wiring, used a multi-meter to test the wires etc and all seemed ok. The 3 terminal plug that clips in at the front of the alternator by the headlight - the orange cable had been damaged and the grey cable had tape over which when I took off had water beneath. Maybe this is what they meant by bodged?

I have repaired the adapter, cut the faulty wire off and crimped it. Car seemed to work perfectly until I put it under some strain again, switch the lights, radio and fan on, within minutes the car was coughing and battery light had come on. battery had also been fully charged this week.

Makes me think the alternator is actually faulty? All the wiring seems to be ok otherwise.

What's your thoughts? If I have missed something with the wiring and I replace the alternator, is it likely to ruin the new alternator?

Thanks,

Alex

[unofix]

Unplug the small connector from the alternator. Start the engine and measure the voltage at the battery terminals. It should be 13.6V as the alternator will have switched to standard charge mode.

Then reconnect the small plug and measure the voltage again. It should not be less than 13.6V if it is then I would say that the alternator is not charging correctly.