Boxster S computer. - 986 Forum

Dhr18 · 03-31-2012, 08:24 AM

I just purchased a 2003 boxster S. it did not come with the cruise control feature. I found some instructions on how to install it. When i looked at the control stalk it said must have the M659 computer. How do you tell if you have this or do all have it?

JFP in PA · 03-31-2012, 08:50 AM

The M659 is the "on board computer" feature, shows outside temp, etc.

Dhr18 · 03-31-2012, 09:23 AM

So I should be able to just install the new control stalk and then get the cruise control onboard computer turned on at the dealer. I should have access to both cruise and the compute functions correct?

JFP in PA · 03-31-2012, 09:53 AM

In addition to having to use a PIWIS to turn everything on, for which the dealer is going to charge you, you should also price out the parts for this, which ain't going to be cheap, plus having to install everything. Last price I saw for a new M659 was over $1500, just for the box..........

Dhr18 · 03-31-2012, 10:05 AM

Would I have to install a new M659? It looks like I can just purchase a new stalk for about 300 and some wire harness. I should be able to install my self. I just was wondering if every boxster had the M659 or if Only certain ones.

JFP in PA · 03-31-2012, 11:08 AM

All 986's carried the computer, but lacked the fourth stalk (which in conjunction of the computer being switched on consititued the "M659 option" from the factory). So you would need to pull the steering wheel assembly off to swap the stalk assembly, plus pull the main dash cluster to add some of the wiring, then have the system "switched on" by a Porsche dealer that is willing to do it (many will not, supposedly under orders from the factory), and actually knows how to (many do not). One thing that will still be missing, if memory serves, it the fancy dot matrix display that came on the cars with the factory option, but your standard display will still work, just not look as cute.

mikefocke · 03-31-2012, 05:07 PM

Weren't there completely different instructions for enabling the OBC for different generations of the Boxster? I seem to remember early models were easy, but later 986s were hard.

JFP in PA · 03-31-2012, 06:14 PM

The later 986's were a little different, but it was mostly due to small wiring changes, and because the factory cars had dot matrix displays rather than LCD. You can find model year specific "how to's" for it on sources like RennTech and other sites.........

Dhr18 · 03-31-2012, 07:09 PM

Thanks for the input. Im hoping to order the new stalk here soon along with the wiring. It hard keeping her to a reasonable speed along the highway so hoping to have it installed soon. Any more advice would be greatly appreciated.

sgt brad · 03-31-2012, 07:16 PM

Hmmm...first I heard of it being this difficult. If cruise is already present as an option does it get easier to add on obc? This was one hack i was interested in doing.

JFP in PA · 04-01-2012, 08:19 AM

Both the OBC and cruise hacks were very popular back in the day, I would call them "fussy" rather than difficult simply because you need to round up a collection specific components, do a fair amount of interior disassembly (see the photo above), and then take the car to a "friendly" dealer to get it activated (some have discovered that this last step is often best done first) in order to get everything you bargained for in the mod.................. Porsche AG has not been very helpful in this vein, telling dealers not to activate the systems post delivery.

sgt brad · 04-01-2012, 07:31 PM

Thanks for the clarification. So turning iton before doing the mods still allows it to work once the wiring is all done? I will go that route. Btw does the durmetric turn on any of the features or do you have to use the piwis? Sorry for the thread high Jack

JFP in PA · 04-02-2012, 02:33 AM

Turning it on first is fine, and is often the hardest part to get done as the dealers tend not to cooperate on doing this. I've never tried it with the Durametric system.

apswater · 07-01-2015, 03:54 PM

It is very easy to turn on. The dealer would not turn it on. They ever said it could not be turned on.

I purchased a Durametric Professional cable. Plugged it in with my lap top went the to control panel settings and turned it on. It was that easy.

Durameteric has 2 different cables.

One is the Enthusiasts Version which will allow you to do 2 cars. (it must store the ID's) That version allows you to turn on the OBC so you can add that stack but it dies not allow you to turn on the Cruise Control.

The Professional version lets you do unlimited cars and you can turn on the OBC and the Cruise Control.

I bought the enthusiast one first but when I found out about cruise control they gladly took it back for a full refund and I bought the pro version. Now I just have to buy the stack of 4 switched, do the wiring and I got all the features I want for my Boxster S.

The Durameteric also give you full diagnostics so it is well worth it.

Porsche Diagnostic Store | Durametric Software Products for Sale

Now I am ready to help others in the area who need help.

NewArt · 07-02-2015, 03:12 PM

Find an indy that works on p-cars. He'll have the stuff to turn on the obc. It was the first mod that I did on my car. Not difficult. 4 stalk from eBay.

Doug427 · 11-13-2018, 06:08 AM

So I'm resurrecting this thread from the long dead.....
Lets say I have two cars in my garage (good chance I am about to). One is a 2002 S, the other a 2001 S. The 2002 has the on board computer with the 4 stalk and the proper display screen on the tach. The 2001 is a much nicer and lower mileage car, but does not have the on board computer system installed. Based upon my understanding of this old thread, I can transfer everything over to the 2001 S and turn it on with the advanced Durametric system.

The question is, if I transfer the instrument cluster from the 2002 to the 2001,, will it display the proper mileage of the 2001 or the higher mileage of the 2002 that it came from?

What problems arise from this transfer that I am not seeing?