4 replies to this topic

[mini1430]

Hi

 This is the first time i have used the forum and would greatly appreciate any help/advice.I have a 1992 Rover Mayfair 1275cc carb model,manual gearbox.I have fitted a brand new alternator from a recognised supplier only to find that I don't have a red dash light anymore when the ignition key is turned on.Please help!

Thanks

Sorry forgot to mention that the unit is a Lucas A127 70amp unit which is offered as a direct replacement for the standard Lucas 17ACR unit.

Edited by mini1430, 13 August 2016 - 07:01 PM.

[Spider]

With the Engine off, take the Brown wire with the Yellow Trace off the Alternator and Earth it. Turn the key ON but with the Engine OFF and see if the light comes on.

 

If it does, then there's a fault with the Alternator, if not, then there's a fault in the car somewhere, maybe start by checking the lamp itself.

[mini1430]

Many thanks for your advice will give this a try and recheck all the wiring,

Best regards

[mini1430]

Hi Moke Spider

 Carried out the test as described but still no light.The brown/yellow wire does carry power with the plug in the alternator and the ignition on/engine not running.Took a look at the wiring and connectors everything seems ok but the printed circuited is giving me cause for concern,if you swap the bulbs and holder around it doesn't make any difference to the charging light although I have power to the circuit from the white and brown/yellow trace wires.Have cleaned the circuit around the bulb holder and can get a positive test across the circuit in this area,my test light operates but no charging bulb! .

 I had a charging light before swapping the alternator for a new unit which is rated at 70 amps,the car is a 92 Mayfair carb,bit lost on this one now might have to call a sparky in.By and by I noticed that there is a spade terminal on the back of the alternator that is live with the ignition on,unit type is A127 is this the norm also the the two brown wires off the back of the alternator plug are also live when disconnected ign on/eng not running.

Thanks​

[lrostoke]

I'd be making up a test circuit to see if the alternator is working.

 

Make a live from the battery to the large spade connections

 

Then live to a small 12v bulb then from bulb negative connection to the small spade next to the large ones.

 

If the bulb lights and goes off when the engine starts looks like alternator is OK.