ECU / PSM / ALARM - Code Reader ? Knutsford

davidleeowen · Sep 10, 2010

Hi everyone

I have a few probs with my 2001 Carrera and im wondering if anyone can help

Basically the below are the probs i have

aircon - not working (engine note changes when switched on - but looks / sounds like pump clutch isnt engaging ?)
ABS + PSM light on (have changed the brake switch for a new one) still on
Alarm - randomly going off - pleases my neighbours no end

My question is .... i have tried a cheap EBAY OBDII ECU reader but this doesn't say anything

Has anybody got a 'proper' Porsche ECU reader locally (Knutsford - WA16 area) i could pop over an plug in to quickly tell me the codes and hopefully give me a heads up on what to look at ?

Cheers
Dave

Richard_Hamilton · Sep 10, 2010

The most common problem with the aircon is leaking condensers, due to corrosion. You best bet is to take it to Kwik-Fit (don't laugh) and get them to give it a re-gas. If they find a leak they won't be able to do it, but don't charge.

The most common causes of false alarm on the alarm system of earlier 996's are water in the tilt sensor - to the right of the battery as you look at it - and the interior monitoring sensor - in the overhead lighting binnacle. Check the tilt sensor first, as you can usually see the water in it. (The white-ish box in the photo). If it looks dodgy, try disconnecting it. Otherwise, a diagnostic check will show any fault codes.

As for PSM/ABS, you definitely need to get a diagnostic check. It is probably an ABS sensor fault, but a check will show which one.

You could try Mike at Sports & Classics, as he is just down the road from you. If you talk to him nicely, he might well plug in his tester for you FOC, and give you an idea what it would cost if they were to fix it. From what I've heard, he is very approachable.

HTH

davidleeowen · Sep 16, 2010

Hello Richard

Thanks for the reply - sorry im late but have just returned from my hols

I had two new rear tyres fitted (Autopoint in Knutsford "" really good guys highly recommend using them if anyone is local)

They had access to a ECU reader and kindly read the codes for me FOC

The reader said - "brake light switch" - which i presume was logged from when i changed the switch first

It also said - "FR RT revolution sensor" - which im taking as front right ABS sensor - so ill have a quick look clean it along with the plug first etc to see if it clears etc ...... but ill guess a new one will be required (cheapest ive seen is £43 quid on design911 website)

Thanks for the info on the alarm - ill have a look at the tilt sensor first and let you know what i find

What is the defects rgds the interior sensor ? ... Water ingress again ?

Also - can either or both of these be disconnected and then the alarm activated still (albiet with faults) to see if it still randomly goes off ??

The reason i ask is the alarm goes off sporadically, so im trying to trouble shoot the offending item

I like your turbo btw !

Cheers
Dave

Richard_Hamilton · Sep 16, 2010

The interior monitoring sensors just seem to go sporadically - it shouldn't be water where it is located. On the other hand, the tilt sensor is in a 'wet' area, and they often fill with water over a long period of time.

You can disconnect the tilt sensor, which wouldn't show any faults, as it is an add-on to the alarm system for the UK (and Belgian) market only. An easier way to find out if the problem is with the interior sensor is to double-lock the car with the remote or key. This disables the sensor. You will get a beep from the alarm horn when it locks.