Okay, I have searched the forum and got some info on what to check, but just wanted to see what you guys would do.
My problems:
Drove the car and noticed low voltage - like 12.4-12.6 while driving with nothing really on. Then wouldn't start the next day.
Had the battery tested - bad cell in it, so I replaced it.
Tried again, same thing. So now I think its the alterantor (makes sense).
Replaced that with a brand new one last night and drove it. Still at 12.7 or so with lights on, but would go over 13 volts with more throttle. But basically too low in the 12.6-12.7 volt range.

So I have a new battery and alternator and still low volts. I did notice that the rear plate light is not working (put a new bulb in it too), and a whack to it made it kinda flash on for a brief second. Maybe something to this? Seems to be not working the same time as the low volts . . .

What and where should I check?

 

BTT

 

check your earth cable mate

 

There was quite a lenghty post on here recently (can't remember who by now.. - may have been Jim Green? ) regarding this subject, and turned out to be the fuselink wire tails that connect to the battery + terminal had gone bad and high-resistance.
However, this was on a Sapphire, so I guess may not be the same arrangement on Escort..
I would be checking the earth leads from battery to chassis, and battery to engine block/bellhousing. Also check the positive wires from the battery for evidence of a similar situation as above.

 

ah, here we are...

https://passionford.com/forum/viewto...903&highlight=

https://passionford.com/forum/viewto...413&highlight=

 

have you checked this by putting a multimeter over the terminals of the battery or are you just going off of a gauge/secs

rememebr its possible that your gauge could be faulty or the feed to it/the secs

iirc spadge had this problem

 

I am 99% sure Escort has these same fuse links.

 

aghhh so your not 100% then.mmmmm

 

Tonight I will check the volts at the battery and the alternator. I'll also have a look at the earth cables.

What about the plate light not working? Anything to check here - is this the same fuse/line as the alternator or something?

 

ESCORTCOSWORTHUSA : Check if it has fuse link tail wires that go to the battery. I spent days checking everything and doing exactly the same as you have. New Battery, New Alternator, only to find out it was the fuse link wires. My car is very low mileage and is kept in dehumidified storage, so just coz the car is well looked after dosent' mean these don't corrode. And the worst thing is, they look ok when you look at them.

I changed all three for 35amp wire, and put an inline fuse in each circuit (45amp) and I now have full power back to everything.

Jim

 

Well - looked over everything, checked the grounds - good ground to the batt and engine.

Tested the car - good volts 13.8 or so driving. Midway thru the drive - volts went to 11.2 -- bad . . .

I checked the volts at the battery. Engine off - 12.15 or so. When engine is running it goes to 11.8 and the SECS monitor reads 11.6 or so.

New battery, new alternator, and worked fine for a ten minute drive till all of a sudden . . .

My rear liesene plate light is not working and doesn't seem to be getting any volts to it - maybe something to that?

Should I pull out all the fuses for lights and stuff and try to check each one?

Maybe bad cable to alternator? Does the cable go from the alternator right to the fuse box?

 

Looking at the wiring diagram, there are 3 fuses all next to each other at the battery.... an 80 amp and 2 60 amp fuses.... cable colours are red to the 80, red/blue trace to the 60 in the middle and red to the 60 next to that..

According to the diagram, the other side of the fuses to those wires (so basically they are connected to the buzbar that bolts to the battery terminal without going through any fuses) are the cables that go down to the alternator which ends up as 1 single cable...

Only the battery light goes through the fuse box.....have you connected a seperate volt meter to the battery? Don't go off the SECS for an accurate volt reading...

 

these are the fusible link wires that Jim has sorted.

i replaced my whole loom recently, and also chopped out these fusible links that were looking manky (they get hot and distort the insulation so that moisture can go in there and corrode the wires easily), and replaced them with proper blade fuses.

if you can avoid low voltage problems, you could avoid expensive engine damage through weak fuel pump, injectors, spark.

this is a mod well worth doing now on these old looms, so big up to Jim Green and everyone who helped him sort it out and for posting it up on here for others to share

 

They are actual fuses mate...they're oblong in shape and are mounted to a busbar and are the main live supplies to the fuse box....

Ford did away with fusible links on the Escort and fitted proper fuses so there is no fear of them being over heated and crispy ducked.....the problem lies else where IMO....

If there is only 11.8 volts at the battery then it isn't charging........

Just a thought too....older Fords won't charge unless the battery light circuit is fully operational..... obviously if the circuit is breaking down once the car is running that you're not going to see itcome on to warn that it isn't charging....you could make your own battery warning light as a test just to eliminate it.....take a fused live feed to a bulb (12v , needs to be the same wattage as the bulb in the dash which will be no more than 5 watts) then earth the bulb to the battery warning lamp terminal on the alternator (blue wire)....disconnect the Ford wire temporarily while you do this test.......run the car and the bulb should operate in exactly the same was as the dash lamp bulb......if it charges properly then your fault is in the battery warning light circuit (which passes through the fuse box)......

 

Sorry Daz, I was talking about sierra's, didn't know escos was different

good advice there on the charging circuit

 

Here is the diagram for the Escort Cosworth starting and charging circuits if it's any help........I left them as big as possible for as much detail as possible.

 

No worries mate..... They tried to improve over the Sierra.....tried!

 

The likely possible voltage drops are going to be:
Between battery neg terminal and engine
Between battery neg terminal and chassis
Between battery pos terminal and alternator output terminal
Between alternator body and engine (this is effectively the alternator ground connection)

So measuring the voltage between these positions (ideally there should be no measurable volt drops) should narrow down the location of any problems

 

one phrase - MK5 fusebox... LOL

good advice though Daz

 

Damn Damn good advice there Daz

 

Mk 5 Joke box....swear box...abuse box...pretty piss poor really but the only reason why they fail as a general rule is a dry soldered joint inside so repairable....unless you get some knob jockey windscreen fitter who doesn't seal the screen properly and it pisses water in over the top of the fuse box!!!

 

Stu,

I'm setting off to yours in 2 shakes of a dogs dick....

 

true - OK for you and me to say, but average punter has got no chance of diagnosing/finding/sorting it

 

Stripping them down and replacing every diode, buzbar, relay, fuse and multiplug back where it came from!!!!! Nice job!!

 

Good, got a cossie here with voltage problems

 

Woops, I left all my meters at home!!! What a shame!

 

How longs it take you to shake a dogs dick twice FFS? Its been 15mins now!!




























See ya soon, kettles ready

 

I said I would be setting off by the time a dog has shaken it's dick twice...I never said when it would start shaking it!

I'm on my way!

 

Could the problem with the license plate rear light have anything to do with my troubles? Maybe a shared line?

Could a bad ground to the light draw that much voltage?

 

IMO, the light problem is not the cause, although there is a possibility that the root cause of the low-voltage problem could be affecting the light. .

 

Status report - still no joy . . .

Here's where I'm at:
Alternaotr - tested and good - also shows 13.8 when engine running.
Fuse link wires - tested and good
Batt idiot light works off alternator.
Still get 12.5 when engine running.

I didn't note this before, but I have a kill switch on it (rally car).

So here's how my setup is:

Battery in trunk grounded to body and pos line goes into kill switch. Other side of switch is two lines - one to starter and one to fuses on engine bay. Then pretty much standard from there. I get the 12.5 volt reding at the fuse box in the engine bay and cabin.

When engines off - I get the battery reading it's 12 volts and same at fuse box and alternator.

Somewhere I have a bad cable- which one????? Car worked fine for two years otherwise - now just won't get the voltage right. . . .

 

BTT!

 

Are the earthing points good? Are the earth cables big enough?

You should have a massive earth cable from battery to body and engine to battery/or body....

 

My fuse link wires read good on ampage, but after spending close to a week going through everything and buying a new battery, new alternator, and still having low voltage throughout the car, I thought I take a chance on Daz'z suggestion on replacing the three (On a Sapphire Cossie) fuse link wires.

30 Minutes later....... Hey Presto, full voltage on everything.

I'f I'd just taken Daz'z advice in the first place I'd have save the price of a new battery and alternater.

The reason I didn't take Daz'z advice first was that the fuse link wires checked out ok on the amp meter ???? But then again the Voltage/amp meter probably puts only a few volts throught the wires to check the ampage. Start putting a real 35amps through there with all the anciallaries switched on and it's a different story.

That was two months ago, and no problems since.

Cheers Daz, I certainly owe you a very large glass of amber nectar.

 

Ok, I'll take your advice and cut those fuse links out - I have one set of them (3 fuse links that go to a medium size red wire) and only this set. Your 35 amp wire and 40 amp fuse replaces all three wires or do you have three sets? I already did cut them off once (and was going to bin them and just put a connector on the red wire), but after reading your post, I reconnected it - after testing out ok, for safety.

Would it really hurt if I did just put a connnector on the red wire? (it's the one that gets connected to the battery side of the of the engine bay fuse box) I believe you call it the busbar side (basically the side that the wires wind up connected to the metal sheet on the side of the box).

Remembering that I have a master FIA kill switch in the line anyway that has a ground resistor on it to abosorb some of the power after switch off.

????? If there where other fuse links in the orginal wiring layout, I don't have them now anyway, so somebody must have thought they were a bad design before me.

I just want the damn thing back to how it was two weeks ago - 13.7 or so volts!

Thanks again from a non-electrical golf pro/ rally fan!

 

The Escort doesn'y have the link wires...just fuses....I can't see the fuses being a problem as long as all the connections are clean and in good order with a decent contact surface area on the battery terminal.