12s Wiring

[AndeeeH]

As its a little quiet in the lower reaches of the forum I hope its OK to post this in here: I want to wire a 12S towing socket in to my 2002 Mk3 2.0 Maverick. It is the type that has the relay near the battery and needs a 'trigger' feed from the ignition to switch the relay. I've been told that the wire must be live with the ignition but NOT when the engine is cranking and that one of the thin wires attached to the alternator should fit the bill. Looking at TIS there are 3 thin wires in one plug on the alternator two of which (brown/white and grey/orange) go to the 'Powertrain Control Module' and the other yellow/black which goes to a 15amp fuse in the 'Battery Junction Box'. There doesn't seem to be a wire that directly links the ignition warning light to the alternator like there is on the 3.0L Maverick. Could anyone say which of these wires I could use or any others that might work. :23: Many thanks, Andy.

[AndeeeH]

OOPS!!! Having tried to investigate the above problem further I seem to have caused some sort of mal-function. :( I connected a volt meter to each of the 3 wires in turn with the ignition on and then again with the engine running. The grey/orange wire showed a dim 12v both times, the brown/white wire showed nothing both times and the yellow/black wire showed a strong 12v both times. Not really thinking about it I then plugged the connector back into the alternator with the engine running. On starting the car today everything seemed fine until after 30 secs. the alternator warning light came back on and stayed on. On further investigation when the ignition light comes back on it is accompanied by the revs. dropping and the engine working harder. Has anyone any ideas what the problem might be, apart from 'If you dont understand it fully, leave well alone'. All info greatfully received. :( Andy.

[popeye2755]

Andy, what do you mean by "The grey/orange wire showed a dim 12v" I thought you were using a voltmeter? Or are you using a "voltstick" bulb thingy?

 

Cheers

 

 

John

[AndeeeH]

Hi John,

the tester is a 'Steinel' Master Check 3 which has an insulated metal probe at one end of about 1 mt. of wire and at the other end is a handle with another probe and a series of lights -6 and +6 side by side then more lights for 12, 24, 50 etc. volts. When I said a 'dim' 12 volts I meant that the -6 light was bright and the 12v light was just glowing, in comparison to the 'strong' 12v when both the -6 and 12v bulbs were glowing brightly. Hope this helps you to help me. :) Andy.

[tomy]

Ive just fitted a towbar to my mk1 galaxy and it came with an" intelligent relay" for the 12 s socket the wiring to it is a main permanant 12v+ supply (30amp) which was prewired in my car to the rear multiplug for the towbar it has a permanent 12v- earth then it has 3 wires off it to the 12s socket one is permanent live for the caravan internal lights , one is to the fridge and one to charge the caravan battery, these last two become live when the engine is running, due to the power surge from the alternator telling the relay that the car is now running so this relay has no swiching wire to activate it . Saved me the time and hassle running an extra wire from front to back to operate it. :wub: