like this one i think? or like it , 

Hi Ian, Peter,

My local Ford dealership is Days and they are the only ones from Carmarthen to Bridgend which are authorised Ford dealers.  I've been looking at previous Fiesta fault reports and anything involving the wiring loom had "replace loom" on it, it appears Ford do not allow them to just replace the connector (which is a nice little money spinner for them). 

The connector appears to be a standard 6-pin connector with M+, M-, P1+, P1-, P2+ and P2-, unfortunately I can't seem to find a supplier of them anywhere via Google, looks like it is something specific.

Currently, apart from the one error on Monday, the car has generally behaved itself.

As for testing the pins, on the throttle body I gave them a gentle prod with a jewelers screwdriver to see if there was any looseness, on the cable connector I had nothing small enough to go into the female connectors on the plug as they are very narrow (too narrow for the screwdriver) but in moving the connector I didn't feel any play in any of the cables.  I didn't pull on the cables themselves but from experience with molex-type connectors on computers, if the female connector is loose then there will be a tendency for a cable to either withdraw or insert slightly into the connector body itself when moving the cable, the cables on this one seemed tight.

as for securing the cables in a single position, that is a good idea, although I suppose I should be careful not to put any undue strain on the cables or connector itself.

My gut feeling is that one of the pots is faulty on the throttle body (possibly wear-related as the car is now on nearly 60K miles) and isn't giving a voltage in range of the other pot periodically.

If it was possible to get the actual male and female connectors for the TPS then a simple test would be to wire a male connector to a female one so that the P1+ and P1- on the female end was connected to P1+, P1-, P2+ and P2- on the male, then insert this between the TPS and the TPS wiring connector, effectively feeding the PCM the value of one pot to both feeds, since the values would be the same then it should stop giving an error.

Kevin

11 hours ago, iantt said:

like this one i think? or like it , 

Hi Ian,  Yes that is similar to the one on the TPS, however on my connector it doesn't have the locking connector (the red bit on top).  Whilst there is a locking connector on the MAP sensor connector, the TPS connector has a bit you press before 'wiggling' the connector a little. I can't recall from memory whether the holes on the connector were more central and longer and thinner on the TPS too, but I think they might have been. If the car plays up again and I take the connector off I will get a photo, it's a little hard to get to as there are some pipes in the way and I have to contort my hand to get to the connector.

2 hours ago, SwanseaS1600 said:

If it was possible to get the actual male and female connectors for the TPS then a simple test would be to wire a male connector to a female one so that the P1+ and P1- on the female end was connected to P1+, P1-, P2+ and P2- on the male, then insert this between the TPS and the TPS wiring connector, effectively feeding the PCM the value of one pot to both feeds, since the values would be the same then it should stop giving an error.

These car connectors are usually customised, they have the quantity to do that. Photos will help, the camera can get into places you can't. But needs good lighting & maybe macro mode.

There is another way in, from the PCM end. I am not sure where your pcm is, in the Focus it lurks inside the air intake ductwork behind the nearside headlamp, in front of the roadwheel. Should be possible to detect it by the fat cable loom going into its hiding place.

I sense you are familiar with connectors & multimeters etc, it is the nuts and bolts and pipes and stuff in the car that is the problem. And it can be a big problem too, I know!

I case you can get to the pcm, I have attached the throttle body to pcm connections. The other end of the wires I posted above, on July 12. Then you can do continuity checks with the possibly dodgy connector in place.

(These diagrams are for 08 to 2013 Fiesta, but I am not sure which engine, apart from it is petrol. Check the colour codes if you can. One unclear number is TPS SUP is pin 6 on the throttle end, & is YE-VT or yellow-violet)

Hi Peter, I read in some Fiesta's it was behind a panel near to the passenger footwell or even behind the dashboard. 

I think I need to get hold of the Haynes fiesta manual before I start pulling bits out, just in case I mess things up, there are 3 bolts currently in the passenger door when trying to re-attach the wing mirror so don't want to yank something out thinking it's the right bit when it isn't!

Electronics and computers I am fine with, mechanical stuff and I am a total liability!

Kevin

pcm should be next to battery

with a security bolt holding a shield in place to prevent connectors from being unclipped. good luck.

Thanks Ian,

there's what looks like a fuse box with some relays next to the battery but I'll have to take another look. By a security bolt do you mean some awful torx style thing where you can seldom get a bit to fit it?

Kevin

1 hour ago, SwanseaS1600 said:

security bolt ...

 

I have had a quick look around, the probability is that it is a headless bolt (sheared off during fitting), that has to be drilled out!!

Worth a quick look to see if it has been removed or changed, but may be too much trouble for this test if it needs drilling.

Is it safe to put your hand on the throttle body connector with the engine idling? Any hot pipes or moving parts? Bending the wires with the engine running may trigger the fault light, but this will be a much less sensitive and more difficult test than an ohm-meter.

Open up the harness binding somewhere, locate the wires & tee off with IDC (scotchlok) connectors?

Follow through the harness, and see it there is another connector? (none show on my drawing, but that could be wrong.)

With a mating female connector, it would be possible to test the valve (pots) in situ. But testing the cable while it remains connected to the pcm (but disconnected from the valve) may not be possible.

Yuk. I am running out of useful ideas. It may either be: risk the garage changing the wrong part (cable / valve), or drill out that bolt. It may need a guide bush made up, know anyone local with a lathe? (I have one, could make a drill guide if I knew the exact dimensions!.)

 

Hi Peter,

you've given a lot of useful ideas and thank you for them.  I'll have a look in the engine bay this weekend but don't want to go down the route of drilling out a captive bolt just in case I slip and drill through the PCM (which would definitely be an expensive fix).

I've looked at pictures of the wiring loom (there are some 2nd hand ones available on eBay) and it looks like the cables are contiguous (and something I would never have a hope of ever changing myself - a rats nest comes to mind).

I can try moving the cables with the engine running, there are some hot areas nearby so I will have to be careful though.

Thanks

Kevin

Has anyone had problems in a s1600 when u drive along your revs die of and the come back 2-3 mins later had new coil pack, full servie and all the air side check and resealed but its still doing it and its gotthe garage where i take it to confused they dont no what it can be any help