Earth Points Diagram

[andy_1984]

as title, looking for a diagram or list of earth points for my model of focus after mechanic diagnosed some erratic idling and flickering lights down to it possibly being a bad earth. so the hunt begins

[artscot79]

as title, looking for a diagram or list of earth points for my model of focus after mechanic diagnosed some erratic idling and flickering lights down to it possibly being a bad earth. so the hunt begins

depends what you mean by erratic idling if you mean the idle goes from 670 rpm to 730 rpm this is normal and has to do with the ecu hunting for the lowest emissions flickering headlights at night and on the dash is due to the alternator being routed from the battery through a 7.5 amp fuse which causes the alternator to pulse nowt to do with earth points ford sell an upgraded wire which goes from the posirtive on the battery to the back of the alternator to correct this its a well known issue and ford have a technical service bulletin regarding it on the focus and the mondeo the wir ecosts about £18 from ford this will cure the flickering headlights the idle on some cars gets smoother as the alternator is no longer pulsing

qoute from service bulletin Should a customer express concern about flickering headlamps, wavering illumination of the instrument cluster, interior lighting and audio unit the probable cause is an extremely high resistance in the battery wiring harness from the central junction box (under the bonnet) to the B+ terminal on the alternator. To rectify the concern an additional cable should be installed.

The high resistance from the 7.5A fuse to the alternator multi plug causes it to "pulse" so the new loom does away with this by taking a new feed direct from the main battery cable on the back of the alternator. !!

[andy_1984]

i posted a while ago regarding this issue but it never lead to such an in depth explenation and makes complete sence. will get the new cable and see how it goes.

with the erratic idle it is as you explained the only thing that is strange about it is that it gets to a lower point in the revs the engine chuggers a little like its about to stall but never does as the revs rise a little again. this doesnt happen all the time it happens roughly once a day for a few hours or not at all.

and there is a pulsing sound coming from around the air box.

cheers buddy

[stef123]

depends what you mean by erratic idling if you mean the idle goes from 670 rpm to 730 rpm this is normal and has to do with the ecu hunting for the lowest emissions flickering headlights at night and on the dash is due to the alternator being routed from the battery through a 7.5 amp fuse which causes the alternator to pulse nowt to do with earth points ford sell an upgraded wire which goes from the posirtive on the battery to the back of the alternator to correct this its a well known issue and ford have a technical service bulletin regarding it on the focus and the mondeo the wir ecosts about £18 from ford this will cure the flickering headlights the idle on some cars gets smoother as the alternator is no longer pulsing

qoute from service bulletin Should a customer express concern about flickering headlamps, wavering illumination of the instrument cluster, interior lighting and audio unit the probable cause is an extremely high resistance in the battery wiring harness from the central junction box (under the bonnet) to the B+ terminal on the alternator. To rectify the concern an additional cable should be installed.

The high resistance from the 7.5A fuse to the alternator multi plug causes it to "pulse" so the new loom does away with this by taking a new feed direct from the main battery cable on the back of the alternator. !!

i wonder if the ford parts guy on here can get this part...i will need to go ask him.

[andy_1984]

with regards to the mention of audio equipment i have had no problems with my 3rd party audio system, however, when i plug my ipod in to the cars cigarette lighter socket to recharge it i get tons of noise through the Speakers when pluging it in to the cd player aux in.

is this the similar problem with audio unit ?

also. is there a part number listed on the tech bulleting im finding it hard to find anything regarding it on the net

[artscot79]

with regards to the mention of audio equipment i have had no problems with my 3rd party audio system, however, when i plug my ipod in to the cars cigarette lighter socket to recharge it i get tons of noise through the speakers when pluging it in to the cd player aux in.

is this the similar problem with audio unit ?

also. is there a part number listed on the tech bulleting im finding it hard to find anything regarding it on the net

the audio sounds like an earth theres one behind the stereo there is 2 in the engine compartment on the passsenger side above the wheel well next to the battery and just under the airbox theres one next to the power steering pump as well undo the bolts and sand the areas down to nice shiny metal and then try after that

[andy_1984]

thanks for the info on the audio prob. i buffed up the earth points you mentioned and its now fine ;)

as for the battery wire, is their any specific guage of wire. plus ive been doing a bit more digging and seems its a wire with a ring connector on one end. seems the price is a bit steep for a wire with a ring connector!.

from what ive read about doing the fix you solder on to the red wire about 10cm from the multi plug and connect the ring connector to straight to the battery possitive ?

so what about the wire with the 7.5a fuse does the existing wire get left as is and fuse bypassed completely?

[artscot79]

<br />thanks for the info on the audio prob. i buffed up the earth points you mentioned and its now fine <img src='http://www.fordownersclub.com/forums/public/style_emoticons/default/wink.gif' class='bbc_emoticon' alt=';)' /><br /><br />as for the battery wire, is their any specific guage of wire. plus ive been doing a bit more digging and seems its a wire with a ring connector on one end. seems the price is a bit steep for a wire with a ring connector!.<br /><br />from what ive read about doing the fix you solder on to the red wire about 10cm from the multi plug and connect the ring connector to straight to the battery possitive ?<br /><br />so what about the wire with the 7.5a fuse does the existing wire get left as is and fuse bypassed completely?<br />

<br /><br /><br />

from what i know the original wire is left in place the wire to the battery is simply to steady the current out a top up if you will

[andy_1984]

so its definetly a direct feed from the positive terminal to the red wire on the multi plug ?

so if i understand this correctly the old red wire on the multi plug runs to a 7.5A Fuse and from that fuse runs to the positive on the battery ?

if thats right shouldnt there be another inline fuse on the new wire as its kinda defeating the purpose of the 7.5A fuse ?

if for any reason the 7.5A Fuse blows theres still an electrical current running to or from the battery that otherwise wouldnt if the fuse had blown.

[artscot79]

so its definetly a direct feed from the positive terminal to the red wire on the multi plug ?

so if i understand this correctly the old red wire on the multi plug runs to a 7.5A Fuse and from that fuse runs to the positive on the battery ?

if thats right shouldnt there be another inline fuse on the new wire as its kinda defeating the purpose of the 7.5A fuse ?

if for any reason the 7.5A Fuse blows theres still an electrical current running to or from the battery that otherwise wouldnt if the fuse had blown.

the fuse is for the multiplug and not the alternator it runds from the bqattery through the fuse to the multiplug to the alternator so all the new wire is doing is steadying out the pulse by supplying the power from the battery as the scs charging system is linked to the dash light etc etc it would need a fuse the new one would not as its the fuse causing the issue and its running directly to the multiplug the old wire and fuse are protecting the dash lights etc and all the other stuff it connects to along the way so you are adding the power after the wiring has passed through all these other things its linked to so old wire =battery- fusebox where it splits to the dash lights etc etc to the multiplug to the alternator the fuse is protecting the other electrics.

new wire= multiplug to the alternator.as its attatched after the fusebox its only supplying power directly to the alternator so no fuse needed

[andy_1984]

still cant find out what gauge of wire should be used, got some free time today and would like to try this fix. anyone got any idea ?

[andy_1984]

thanks for your help artscot, i finaly got around to trying the fix but it didnt solve the problem :(

[andy_1984]

regarding the pulsing sound from around the airbox.

while trying to resolve my misfire problem i accidently discovered that restricting the air flowing from outside in to the engine the sound goes away! whats that all about