SimonT

Following on from my problem with my Mk6 Si.

Some of you know the battery light came - first thought was the altenator was packing up. We ran a volt meter accross it and it was only dishing out 12v's so we bought a new one.

Just fitted it this morning - guess what - problem still there!!!

Something else we noticed as well:

Well the ignition is on (without starting the car) all dash lights are on and the temp gauge goes right off the scale!!! It stays like this when the engine is running too.

The altenator we got is a brand spanking new Bosch item and seems to be working fine.

We have check the wiring for any signs of damage but all seems to be well.

Has anyone got any ideas as I'm close to burning out the bloody thing

ta

ST

rabmc

Sorry matey , i work with wires but car electrics are a different story all together had a wee problem with alarm the other day but turned out it was a blown fuse which was okk , but i suggest u take it along to an auto electician they will fix easy and stop u from doing any more damage and buying stuff u may not need £20-£30 to have a look and probably fix if its not alot and it will it will stop u being in the wilderness about whats going on matey sorry cannot help but this is what i do if its electrical because its messy with all those wires and no one can really be sure what it is unless they are in the no

SimonT

cheers for the info mate. Might have to get the yellow pages out.

someone has suggested that an earth wire might not be on properly?

My old man is a mechanic and this even has him stumped

SimonT

Also the started seems to get its power feed from the altenator.

is this right?

rabmc

LOL , wires and that have that effect on ppl my old car had indicators flashing when i braked and all sorts of stuff after all of us banging our heads together i plumped and took it to a local auto electrician who replaced a broken/shorted wire and took £20 and got it back with in 3 hours so now ive no worrys about this sort of thing cos i just run it along to him (remember they no what it is probably when your explaing it)

SimonT

We have jsut check both wires going from the altenator to the started (both the large red and small black wires) perfect connection (IE 0.00 on the ohm meter)

Dont really wanna call out an auto electrician as round here they are probably dodgey as f**k!

Anyone else got any ideas?

whitneyd

You probably have a short in the gauge pod.

SimonT

Have you got a suggestion of how to check for this?

richm

initially make sure you have a good ground connection between the alternator body and the engine. Measure the voltage between the alternator body and engine block while the engine is running - it should be effectively zero if connection is good. Also measure voltage between engine block and battery negative to check engine ground connection, again should read virtually zero.
Any appreciable voltage indicates a poor ground connection between alternator body/engine/battery negative.

SimonT

OK I think we have found the problem

Lucky enough I know teh previous owner of the car - its my sisters boyfriend.

Turns out he had the eact problem!

He saw us working on the car and new we where going out to get a new altenator but didnt tell us this after we got back

Theres a connector behind the passenger side headlight (see pic below)



NOW when he got the car it was unplugged. He at some point in time connected it back up and guess what - battery light came on and the temp gauge goes right round!!!

We disconnected it and the battery light dont come on but the temp gauge still goes right round.

So we disconnect the temp sensor (pic below)



and the temp gauge does go round!

He then told us that all he did was replace the sensor and it solved the problem. temp gauge worked ok. no bat light and that random connector at the top stay'd unplugged.

My dad admits that when he put the bumper back on he connected that connector back up because it was unplugged

So I just spent 80 quid on a new altenator when this was the problem all along

So my guess is having this connector plugged in 1) causes a short so the bat light comes on and 2) totally cattle trucks the temp sender.

Question:

What is that connector for behind the headlight?

cheers guys

ST

SimonT

anyone?

SimonT

I guess not then!

SimonT

We finally sussed out what was going on!

After spending ages studying wiring diagrams we concluded that the connector would've been part of the air con system.

It wouldve been an optional extra from fords so the wiring is there and should've had blanking plugs in the connectors.

I wont go into details but a new water temp sensor has sorted the problem

Now all I gotta do is kick sis's boyfriends arse for not mentioning any of this before i went out and bought a new altenator!