Richard Hamilton

It is on the cylinder head pointing upwards. As you look at the engine it is on the right hand (driver's) side, pointing vertically upwards, about 2/3 of the way towards the back of the engine compartment. item 32 in the picture.

There are two switches on the clutch pedal. One is the start inhibit switch, which must be working otherwise the car wouldn't start. The other is the cruise switch.

In the picture the two switches look different (16 & 17), but I don't know which is which. You need to check that they both work when the pedal is depressed.

It would also be worth checking that you are getting 12v +ve to the stalk - the black wire going to pin 2 of the 4-way plug.

I have a wiring diagram which shows DME7.2 on a sheet labelled "Carrera (996) Sheet 18 Model 99/00" - I was thinking that maybe some 99 C2's might be 7.2, but maybe the sheet is intended for the 1999 C4.

Richard - my mistake you only get those on the newer cruise control when it is part of the DME.

So, no PST2 tests that I can find for the older version.

That's a relief! I have used the Input signals for eGas cars, and it is a very useful test - especially when you get wires the wrong way around!! There is a wire from the cruise actuator to the diagnostic plug on early cars, but I have no idea what it could be for.

Going back to tmc's problem, have you checked that the brake lights work (as suggested by Tool Pants)? Also, the cruise will not engage if the clutch cruise switch is operated. If it is secured the same way as the brake switch, then it can slip in the mounting bracket and cause the switch not to operate.

Another thought - and this is a long shot - are we sure your car is not eGas? I suppose if it was a very late build in 1999 it might be DME7.2 and we are all barking up the wrong tree. Check your option sticker for (M)620 - if it has then you have egas, and there is no mechanical actuator.

That's interesting. I don't see those options in the Input Signals on mine. I'll have to check the wiring. :unsure:

Yes, Chris - Alarm/Coding/Country Coding.

I tried coding my 996 from "GB with Sunroof" to "US with Sunroof" in the country coding to see if it had the opposite effect on my UK car. Didn't work - I got a fault - "wrong door lock". There are loads of country code options, so maybe it would be a question of trying a few different ones to see if you can find one that works.

Hi Chris

It is 986321 for RoW Boxster S's.

Have a look in the Alarm Coding with the PST2, and you'll see options for RoW/Japan etc. It might be worth trying to select RoW and see if you get the extra features.

The only snag to this might be that the remotes operate on a different frequency, but it is definitely worth a shot.

Yes, I meant the small 4-way connector that connects the stalk to the loom.

The actuator looks like this:

Bear in mind that this is for a RHD car so has an additional mounting bracket.

In a RHD car it fits like this:

The wiring is temporary in this photo, you should have a plug on the end which looks like this:

Here's a simplified wiring diagram:

It would be a hard job to disturb the plug connection. Other than that, I can only suggest checking all the other connections. I'm not sure if the PST2 will show the input signals on the cruise control module - maybe Loren could comment here.

Do you have another remote key? Maybe take the battery out the suspect key and use the other one for a while. At least it would tell you if the fault is with the key remote or the alarm control unit. If that doesn't work, you need to get it checked with a PST2 to see if there are any faults stored in the memory.

Chris

On an '03 you only have to make a connection between the fuse box and the stalk, and the stalk to the cluster. No connections to the motronic are needed.

edit: I have PM'd you a wiring diagram.

On UK spec cars you can raise the windows (and close the sunroof) during locking by pressing and holding the remote button. Also you can open the windows when unlocking by holding the button. However, I would have thought that if you do this then the car would auto-lock after the set time if you don't open a door.

Here's a Quick Start Guide I made a while ago:

PST2_Quick_Start.pdf

And here's how to change units:

Unit_Setting.pdf

Sorry, been on holiday and just got back.

I know it sounds obvious, but have you checked fuse B7? That's the power supply for the cruise. Also, chech that the 4-way connector is in the right way round - it is polarised, but not very well.

I tapped into the cigarette lighter for a switched supply for my speed camera detector - before I knew about the phone prep connector. The nice thing about connecting to the lighter is that the supply is held on when you switch off the ignition, and switched off when you remove the key. Is this the same with the phone prep connector?

I want to disable the 2 buttons on the steering wheel and add my own button somewhere close to the gear selector. Anyone know where/which wire loom to disconnect and tap into the circuit?

1999 996 C2 Tiptronic

I suppose my question is WHY? Or rather, wouldn't you be better to leave the switches active on the wheel, and add an extra switch by the lever?

My old 993 Tip S had the best arrangement with buttons on the wheel, and the lever slid into a "manual" gate. You could shift with either the switch or the lever. At first, I found the 996 arrangement (with just wheel switches) a bit frustrating. For example, when pulling away from a junction in first you invariably want to hit second while the wheel is turning. I found that the way to overcome this was to flick the lever into Auto and back. This makes the upshift but holds it in second. Hope this helps.

No, they aren't illuminated.

Do a search here for "+OBC +retrofit" and see what you get. Also have a look here: http://www.whiteson.org/boxster/mods/obc/

Rich

Chris is right - it is much simpler on an '03. I'll email you a simplified wiring diagram.

Richard

Seems to me like you have two options. Either fit the stalk and take advantage of the OBC, or find someone with a PST2 and have them de-activate it in the instrument cluster coding.

They are 4's, but well done with tracking down the correct part.

This is from the 996 wiring diagram (connectors). It is the only 4-pin connector of this size that I can see. Might be worth a look?

Edit: I couldn't find anything on the AMP/Tyco web site, so maybe the best bet would be to go to a Mercedes dealer and see if they can recognise the numbers in Loren's photo.

That 4-pin connector looks very much like the one used to connect to the cruise stalk, but I am sure you must have thought of that (999.652.972.40).

Any update on this, as I have the same problem :(

Paul

I had the same problem on mine, and had TimeSert thread inserts fitted to repair it. Work was done by my friend Tony Wright (Wrightune in Wallingford) so fairly local to you. Give him a call on 01491-826911 (www.wrightune.co.uk).