1981/82 wiring diagram (row turbo)

[tref]

Gentlefolk...

The Turbo Cab project continues... I have managed to get the fresh air blower fan working... at least when connected straight to the battery, so now would like to get the rest of the wiring to it sorted out. Unfortunately none of the wiring diagrams I have seen correspond with the wiring I have!

The Haynes book of lies shows... well, it's usual token pages... the various Porsche manuals on .pdf online only appear to show the American models... and show a looks like yellow and violet wire from the fresh air blower fan. In my case, and the fan from the spares car, the wires are red/blue, and brown. From my records, the brown was connected to the inboard spade on the heater controls, but as the wiring was hacked, I have nothing for the "live" connection to the fan. As I have two such fans, I am guessing it is typical for a rest of world car, so does anyone have a wiring diagram on which these colours match? Otherwise, any ideas where and with what this plumbs into the main loom? The red/blue wire terminates with a shrouded male spade connector behind the centre console, but I can see anything obvious to match it.

Many thanks for any help,

Tref.

 

[924nutter]

Hi Tref, does your fresh air fan have sliders or rotary controls? That will give a clue as to the year. Something to bear in mind is that with both versions there is no switch in the feed, all the control is achieved with resistors in the earth return, and surprising as it may seem, even in the off position the fan actually still rotates. Also both my 924 Turbos only have a single fan, and I have had the matrix out of the car with slide controls. If you have 2 or mare fans it may well be that you have some kind of hybrid with some kind of air con involvement or the car has been significantly played with, to the inclusion of a different heater completely so the wiring on the motors may not match up at all. I can peer into the wiring diagrams when I know what sort of controls you have, and work backwards.

 

[tref]

Sorry, I confused the issue by saying "two fans" - I compared the one in the car with a spare one I have, that was all! It is the early type, with three sliders, one above the other, fan control combined with the lid-lifting on the upper slider. As far as I can see it is bog-stock 924 Turbo... I don't want to say early turbo because it is still a series II not a series 1, but it isn't the rotary fan control for the fresh air blower.

What I am interested in particularly, is whether teh feed to this fan should be via a relay or not... as it looks like it should be in some of the wiring diagrams, but also, I would like to get it right, and absolutely as it should be (it makes future fault finding so much easier!) and use the right colour wire for the car ( I suspect at the moment something is missing, or incorrectly routed). I have a feeling my problems are primarily just that I'm not looking at the right wiring diagram though... yet!

Many thanks,

Tref.

 

[924nutter]

It may be that on non air con cars the resistors are in series with the input but what I do know is that they are on the slider mount right behind the panel which come out easily. What I can do is have a look at the wiring colours on my "slider car" over the weekend and see what I can turn up Tref. After that you will owe me a pint, as it is a 30 mile drive to where it is sorned.

 

[tref]

Many thanks - I think I owe you a pint or two already - workers conference?

OK... Given a red/blue wire and a brown wire to the fan, it is pretty clear which side is earth! My records mean I know where the brown wire goes on the slide controller (there are two spade connectors, it goes to the one closest to the centre of the car) There looks to be a resistance coil in slide control, so my guess is the other contact just goes to earth. Connecting the live side of the fan to the battery with that terminal earthed caused it to work, so I am pretty sure that is correct. but... that leaves teh live side...

The older wiring diagrams show it going straight to Fuse 10 via terminal D19 on the back of the fusebox, but they also show a yellow and violet wire from the fan. Later ones have a relay for the blower motor supply, which comes from fuse 9 in the additional fusebox. If it has an additional relay... I haven't even a clue which it should be!

So, as always, any further information gratefully received!

 

[924nutter]

How urgent is this Tref, becuase it is peeing down and the car is not under cover. Just thinking about it I would not immediately agree with you that the disconnected spade is earth. There must be different iterations or versions, and I need to check before you make the connection and induce a variable speed short-circuit.[], although you say that by earthing it, it completes the circuit. If your heater fan has input plus earth colours however (i.e.solid brown conductor), then it is clear that the input is controlled, other wise the earth conductor would have an identifying stripe, so the feed must come up from the slider. The confusing thing with all this is that I had (again from a wreck for £250 in M.K.) a 1978 924 n/a that had electric windows and rotary controls for the heater. It had suffered a small melt down in the dash loom, hence the price. My first 924 A32 NFX had come to the end of its useful life at 247,000 miles on the rolling monocoque, so I made one good one out of the two. Unbelieveably the two cars had different wiring even though they both had the rotary heater controls. Contrarily,(I hazard a guess at the year) in 1981 the turbo still had sliders. so it is not guaranteed that my car's colours will match yours, but there is more than an even chance if yours is "W" reg. Also, in an incredible coincidence, the code letters for the wires have not printed properly in my workshop manual so all I can get is brown/?, even under a magnifying glass, for one of the wires.
I have annotations in my Haynes that show how the wiring in A32 NFX differed from the 1981 on wiring diagrams in that the blower fan was supplied via relay 6 so this all needs to be approached with your usual level of care and caution.

On a different topic, when you drive it try to be ultra precise when changing from 4th to third, more important when you are giving it the beans, becuase if you go right across the gate into the R/1st plane and pull back you will damage the combined synchro/baulk ring behind the first gear cluster and then you will not be able to select 1st at all. I confess to being a clutz in this aspect. It is cureable but you have to take the gear box out and clean the burrs off what passes for a sychromesh cone face. If you have old copies of Porsche Post my article about it was published in 2005/6. I have it from Mike Rees on cd-rom if you ever need it.
Out of interest does it have the green digits on the dash dials?

More anon.

 

[tref]

Not urgent really - the car won't be back on the road until May, and if I don't finish this job today it will be Thursday earliest before I get back to it - I would much rather get it right, and understand what it should be. Same here, it is a 46 mile round trip - but I have a nice garage, tea, coffee, and a four post lift to work with - ok, there is only the headroom to get it bout 18" off the ground, but you would believe what luxury that is when getting to the fusebox/underdash!!!

Yes, it has green dials - maybe I was lucky, but apart from where the loom has variously been "hacked" the two turbos (the cab and the spares car) do seem consistant in the wiring, both are W reg.

Have to be very careful anyway with the gearchange at the moment, as the clutch seems to "drag" a bit - it certainly isn't being ragged, let's face it, it is never going to be that kind of car. It is another job on the list to do... Despite that, it is a really nice car to drive - which is a relief given the amount of time that has gone into it!

Did I read it will be next year before you can get on with yours?

 

[tref]

Actually John,

Of more interest to me is where there is a wiring diagram with the wires from the fan being red/blue, and brown - there must be a wiring diagram for a rest of world 1981/82 Turbo, but I haven't seen it yet (and I suspect that will match up with yours and mine!) I suspect there are more wiring diagrams in the genuine Porsche manual than are scanned in the widely available .pdf... I wonder what our club records have?

 

[924nutter]

Having had a good peer at the Haynes, try page 249 current track 93. S10 (fuse) via connector plug D pin 19 on the back of the fuse box to the motor via Bl/R (Blau/Rot). into control switch and to earth. The earth connection should be double connector with both 0.5 and a 1.0 mm cross section conductors in Brown. The 0.5 should trace to page 247 providing earth returns for heater control illumination, speedo illumination, oil pressure illumination, etc. 1976-1977 1/2
or
P262 Current track 1&2 if you find that you have a resistance wire of 10 ohms paired with the conductor from the motor. This would still work if the motor colours were Bl/R in and brown out, because the feed is from S10 and D19. In this instance there would be the similar 0.5 and 1.0 mm pair connecting to the slider control, again with the 0.5 providing heater control illumination, speedo illumination, oil pressure illumination and clock illumination. 1979 including std models 1980. Where I find differences I just mark the haynes according to what I trace out. I have some sections of the genuine Porsche workshop manuals sadly not includng the relevant wiring, the Haynes diagrams seem to be half size photocopies of the originals.

Or wait until the weather improves and I'll have a look at mine during the week

 

[924nutter]

ORIGINAL: tref


Did I read it will be next year before you can get on with yours?

You may have read that last year. I am fit enough to start again. Luckily the workshop where the block has been machined is used to customers leaving engine parts on his premises for years on end.
I have even been out and changed the MAF on the 996T cab.

 

[924nutter]

The club has a workshop manual for the 924 turbo;

To gain access to one or more workshop manuals please contact the Club Archivist, Peter Cook, by email or call 01789 400 832. To make your inspection more efficient, please advise Peter of your PCGB membership number and the manual section(s) that you wish to view. NOTE: these manuals may not be taken away from Cornbury House. (Dates in brackets are publication dates not manufacture dates!)

 

[tref]

Thanks John,

For some reason I hadn't noticed that in the Haynes book of lies! That looks about right to me, so I just need to rummage around the back of the fusebox and check I have a red/black wire, not a red blue wire to a suitable connector (at least in my Haynes book of lies down to the connector is bk/re and from the connector to the fan is bl/re - same page and current track though.

I have to take the 944 belt tensioning tool back so it might be a good oportunity to take a look at the workshop manual then - I'll have to see what I can arrange.

Many thanks again for your help John, nice to talk to someone else that can actually read the current flow wiring diagrams - I love 'em, find them much easier to follow than any other diagram, but it seems we are the exception to the rule!

Right, I'm going to head off and have a look now...

 

[924nutter]

Or you can down load pdf versions here

http://www.2010.cannell.co.uk/manuals/manuals_porsche.html

 

[924nutter]

ORIGINAL: tref

Thanks John,

For some reason I hadn't noticed that in the Haynes book of lies! That looks about right to me, so I just need to rummage around the back of the fusebox and check I have a red/black wire, not a red blue wire to a suitable connector (at least in my Haynes book of lies down to the connector is bk/re and from the connector to the fan is bl/re - same page and current track though.

I have to take the 944 belt tensioning tool back so it might be a good oportunity to take a look at the workshop manual then - I'll have to see what I can arrange.

Many thanks again for your help John, nice to talk to someone else that can actually read the current flow wiring diagrams - I love 'em, find them much easier to follow than any other diagram, but it seems we are the exception to the rule!

Right, I'm going to head off and have a look now...

I am happy to help, it is good to have a challenge and refresh the brain. You should try to get your head around the wiring diagrams for the Citroen AX. Diametrically different but again a piece of cake when you understand how to interpret the markings. In my experience mechanical expertise is more common than electrical expertise. I would have liked to be an electrician but I followed the money and went into management.