URGENT!!! wiring diagram for APU MAF connectors needed

[Geeman]

Car's in for work, and the guy needs a wiring diagram for my MAF. 1.8T APU engine, 2000 model (facelift).

Long story short - I spliced in new wires to replace burnt/melted wires from engine fire. I 'may' have got one in the wrong place.

Any help appreciated!

Cheers,

Giles

 

[aragorn]

G70 is the MAF

Connection [21] joins the same color wires from various other sensors, and then goes to fuse 234, so its a 12v feed to most of the sensors.

 

[Geeman]

Thanks (again) dude, but my MAF has 4 wires going in to it though...

 

[Geeman]

Scrap that... just figured out that the connection at the bottom makes up the 4...!

Doh!

 

[Geeman]

Dude... what's the 'B1' / 200 part on the right of the MAF with the black wire going to it?

 

[Geeman]

Anyone...?

And does that diagram show it as actually connected to the green wire going into Pin5...?

 

[aragorn]

its the shield for that wire, and is connected to ground.

Edit: actually i'm going to verify that for you... black isnt normally ground....

 

[Geeman]

Shield....? What does that mean? Is it actually physically connected to that wire?

 

[Geeman]

The reason I ask is that the MAF isn't producing any kind of reading... it's just reading '0' (apparently).

The only thing we can think of is that when I re-wired (some) the loom, I incorrectly connected the black wire straight onto the green wire. Maybe this isn't correct...?

 

[aragorn]

Ok just checked.

grounds are NORMALLY brown on DIN wiring harnesses but it seems this is an exception, and it IS an earth.

Its a shield or a screen for that wire which basically means instead of it just being a cable with some plastic insulation wrapped round, theres another sleeve of wire around the internal insulation, which is connected to earth, like this:

http://www.summitsource.com/images/products/MSQ100.jpg

Thats not quite the same, but it highlights what i mean, the signal wire is the inner core (copper in that picture), then theres some insulation, then the shield (silver braid in that picture) then the outer insulation.

If you've connected black to green your earthing out the green wire, the black "sleeve" should just stop.

 

[Geeman]

So the black wire shouldn't be physically connected to the green wire then?

Right... I'll whip it off then.

Might have to get a MAF connector from another later car to see how it's all put together...

 

[Geeman]

Right... disconnected the black wire from the green wire... but still showing the same symptoms.

I'll have to trace it all the way back to the ECU on Sunday I think and do a continuity test on each wire to makre sure they're all still in one piece.

Grrrrr!

I WILL get to the bottom of this! lol

 

[aragorn]

well at least your on the right track now.

If the MAF is outputting nothing though, how come there isnt a fault code?

 

[Geeman]

I have no idea...! Electrics are the one thing in a car that baffles me!

 

[Geeman]

So... pins 2 & 4 were in the wrong way round. I had no continuity between connector pin No4 and the ECU or pin No2 to fuse 34. Doh!

Off for a test run now.

 

[Geeman]

No good still.

Found violet wire running from N80 valve had snapped further down the loom. So soldered that up and now there's continuity from the N80 valve to the ECU... so that fault has now been rectifed. Yay!

But now, after disconnecting the ECU, I've got a 18048 code error - Internal Contr.Module (EEPROM) Error

Uh oh...

 

[aragorn]

that doesnt sound very good!

Does it clear?

If not i'd check over the loom again very carefully, and make sure you've not overlooked something.

 

[Geeman]

It's cleared now. No fault codes at all. Yippee!