Technical Weak earth, where to actually clean? Gearbox earth?

[hapveg]

My 2002 Fiat Punto Mk2 8v 1.2 Active has been having problems, some of the dashboard lights show up dimly when they should be off.

Thanks to the regulars of this forum I can say it's almost certainly a bad / weak earth.

I've taken some pictures, I've unbolted, given a scrub with a steel brush, then reattached the parts marked with a blue arrow, but that hasn't fixed it.

The wires shown near the red question mark, they seem ok, but I'd have thought they should be in a sleeve.

A close up of the blue arrow on the right:

The Haynes manual says the dashboard is connected to the E2, E3 and E7. E2 and E3 are in the 'LH inner wing', but E7 is 'On gearbox'.

I'm ashamed to say, but I don't know where to find the 'On gearbox' earth. Is it accessible from the top of the engine, or do I need to go underneath?

I've marked out a grid on a photo, can someone please tell me which section I should look in for the gearbox earth.

 

[Andy Monty]

I love battle ships

if its anything like the fiat panda. fiat 500 and grande punto it might live here

https://www.fiatforum.com/500-guide...lso-includes-battery-removal-upper-earth.html

 

[Ziggy122]

Right - going to the Image where there are the ghostly arrows and the ?

The Arrow pointing to a little black box - is a multi purpose earth
Many items return to earth there

That one should be given a darn good clean

Also giving the negative battery clamp a darn good clean is always a good move

Next the BODY TO BATTERY EARTH
NExt to the little black box i mentioned - its bolted just below the battery, That too needs a darn good clean

Following that Black cable - it sorta dis-appears UNDER the battery and the Clutch slave cylinder
Under there is the gearbox earth
This is how the starter motor earths mostly But tbh if your doing a job, do it properly

Ziggy

Regarding the gearbox Earthing cable
using your grid
IF you enter via N9 its around N7 / m7 ish

 

[flisko]

I love battle ships

if its anything like the fiat panda. fiat 500 and grande punto it might live here

https://www.fiatforum.com/500-guide...lso-includes-battery-removal-upper-earth.html

haha u reminded me of

 

[fingers99]

I've seen neater wiring on the Bismark -- and that was blasted to bits and left on the bottom of the sea for 60 years.

Generally, the gearbox earth runs from the selector plate, on the top of the box to the inner wing. On the gearbox it's a 6 or 8mm stud.

But so much of that needs cleaning off, coating with silicone grease, and re-attaching.

 

[oldhammer]

did you take the top off the earth block?

the top comes off and earthing connectors are inside,


there is another earthing point behind bonnet catch in car iirc,

 

[Ziggy122]

did you take the top off the earth block?

the top comes off and earthing connectors are inside,


there is another earthing point behind bonnet catch in car iirc,

i dont tend to pull that connector off - its the rust on the lug that attaches to the body

As for the internal one on the car near the bonnet pull - i've never seen it

ziggy

 

[oldhammer]

i dont tend to pull that connector off - its the rust on the lug that attaches to the body

As for the internal one on the car near the bonnet pull - i've never seen it

ziggy

they go green inside, ithink its Brass coated contacts,
the one in boot goes same way,

 

[oldhammer]

(As for the internal one on the car near the bonnet pull - i've never seen it


its well hidden,

ipulled mine to bits to find all the earth's.
i is no good with books and puter's so ipulls things to bits to see how it works,

as they say 'seek and you shall find,

 

[jackwhoo]

Measure the resistance between mounting lug for earth points and earth at heater and if there is no real resistance you don't have to open it up.
Though it would be interesting to see inside.

 

[jackwhoo]

It could be you have to undo it from car and top is a cover which lifts up off base.

 

[s and b]

OK so I am supposing I found where my heater Earth orginates at the black connector just in front of the battery.

How do I release those bloody clips shown in OldHammers photo?

https://www.fiatforum.com/attachment.php?attachmentid=136124&stc=1&thumb=1&d=1399503567

I cant believe it. I have the thing in my hands and I just cannot get it apart:bang:

Possibly it is stuck together with a professionally applied undersealer and I am just going to have to rip it apart..

as with all these type of clips you need to waft them with a heat gun to make them pliable again
ive just spent 2 days removing a wiring loom in situ on a renault with the aid of my trusty gun ive still got cuts and scrapes on my arms and the mother of one massive bruise full of all colours of the rainbow

 

[judderbar]

as with all these type of clips you need to waft them with a heat gun to make them pliable again
ive just spent 2 days removing a wiring loom in situ on a renault with the aid of my trusty gun ive still got cuts and scrapes on my arms and the mother of one massive bruise full of all colours of the rainbow

Thanks. I managed to get it apart using brute ignorance. Strange that such an important multi earth is not directly connected to the battery and instead relies on the bodywork to get an Earth from the other side of the battery.

 

[judderbar]

Measure the resistance between mounting lug for earth points and earth at heater and if there is no real resistance you don't have to open it up.
Though it would be interesting to see inside.

Sorry I deleted my post after i got it open and I thought nobody had replied.

I found the cigar lighter Earth and the door hinge gave me a better Earth than the heaters Earth which is switched and so is not directly jumpable, so I assumed this Earth was faulty.

 

[judderbar]

it would be interesting to see inside.

Here you go. It is marked inside in tiny letters C10. The wiring is identified with letters and numbers where the wires enter the connector.

It is a fairly fancy water proof connector which I think could be completely reworked if you had the tool for removing the wires.