Canbus decoder - 996 C4S 2002

Canbus decoder - 996 C4S 2002 Hi, has anyone had any success with any CANBUS decoders for a 996? I'm trying to replace the factory CDR23 MOST radio with a double DIN kenwood nav unit, and i'm really struggling with the CANBUS. I've tried 3 different decoders now, 2 from connects2 (STK445 & STK551 - one is for a 997 & one for a Cayenne) and a Dietz 66030, but no joy with any of them.. I need the canbus decoder to give me the switched live, Illumination, Reverse, and handbrake signals for the new headunit without having to hardwire everything or hack/cut/splice anything on the vehicle harness, it should in theory simply connect to the permant live & canbus high/low from the factory radio harness, and provide these outputs.. I've tried getting help from Connects2, but they just recommend to take a switched live from elsewhere & do without the rest... The rest of the Connects 2 stuff seems to do the job, the MOST decoder works OK taking the RCA feed from the new headunit & retaining the factory amp & speakers, but the CANBUS stuff has beaten me... If anyone has managed to get a canbus decoder to work, i'd be really interested to know which one.. Thanks in advance for any help you can offer.

Welcome David! I'm guessing that if your car has the MOST bus, it is MY2003. Check 10th digit of the VIN. (2=2002, 2=2003). I think you'll find that the available CAN signals are a lot less comprehensive than in the 997 and later Cayennes, which have a separate CAN controller. The Comfort CAN controller in the 996 is incorporated in the instrument cluster. Basically, it only communicates between the cluster, radio, and air conditioning. You might get the signals from the Drive CAN, but it would still mean wiring into the Drive CAN somewhere other than the radio. There is no switched supply at the black radio plug, but there is a speed signal (grey/pink wire) and backup signal (black/blue). For the handbrake signal you have to connect to the handbrake switch itself, and you can take a switched live from one of the orange wires on a bridge plug on the back of the relay panel, or at the fuse box.

Thanks Richard, yes it is a MY03 car. You mention a backup wire - is that the same as the reverse signal? i.e. +12v signal in reverse? Thanks again

Yes, it is the reversing signal. It is just marked backup signal on the wiring diagram. I assume it goes live when reverse is selected. It should be easy enough to test.

This post is most useful but a question to Richard or anyone who can explain. Pcm 2 on my 04 booster has a can connection . The A plug has No switched live the position pin 7 isn't populated. So how does my pcm switch on if not via can comfort lines? I am running into the same issue as the op in so much as the decoder I have for my android auto unit doesn't seem to power on the unit. It must be possible if pcm2 does it? Can someone shed light on how else my pcm2 is turning on without a switched live at pin 7 of plug A ???

Thought it worth adding , if I run a switched live it all works fine and I think some of the can functions do work , specifically switch off on door open which I think is can controlled ? I am leaning on the thought that the can protocol script doesn't work quite right ? The file it's using says Cayenne rb58 or something similar. I wonder if the 996 script/ protocol is different ?

Okay still looking for answers to does anyone have a working van bus decoder for 9x6 android head unit? I've done some more playing around and my original protocol is BG Cayenne BG.XP when using the protocol print function in the factory settings menu I get a single line of what looks like rubbish. However if I change the settings to RZC (raise) PQ Low and view the protocol print on screen I get scrolling lines of what might be useful can data . My thoughts are that I still don't have a working protocol for the decoder . I wonder if anyone has the decoder files for a working pccm plus ?

So further to my rambling. My decoder box is marked can bus decoder Porsche . Despite this these boxes are fairly universal and how they work is dependent on the protocol they are loaded with. My box doesn't work with my 986 but the box itself is not at fault . If I use a VW can bus id for ignition key on 0x271 and feed it the correct can data I can get the box to operate it's 12v switched live feed . Obviously the can id for ignition key on for the 986 is not 0x271 . I would guess you can try as many boxes as you like but if they aren't loaded with the correct protocol to translate the 986 / 996 can id's you won't get anywhere .

I think its best to hard wire. this is the 996.2 canbus info supplied by 911uk member that i got hold of for another project. Address 0x4E0 Oil temp, start bit 40, length 8, intel byte order, unsigned, factor 0.75, offset -48 (-48 to 142.5 degrees C) Address 0x298 Intel air temp, start bit 8, length 8, intel, unsigned, factor 0.75, offset -48 Address 0x520 Oil pressure, start bit 32, length 8, Motorola unsigned, factor 0.04, bar Ambient temperature, start bit 24, length 8, intel unsigned, factor 0.5, offset -40 Address 0x280 Throttle position, start bit 40, length 8, intel, unsigned, factor 0.390625 Engine speed, start bit 16, length 16, intel, unsigned, factor 0.25, RPM Address 0x289 Coolant temp, start bit 8, length 8, intel, unsigned, factor 0.75, offset -48 Address 0xC0 Steering angle, start bit 4, length 12, Intel byte order, signed, factor 0.390625 Address 0x2A8 Wheel speeds, all length 15, intel, unsigned, factor 0.01, km/h FL start bit 1 FR start bit 17 RL start bit 33 RR start bit 49 Address 0x1A0 ABD intervention, start bit 3, length 1, intel TCS intervention, start bit 0, length 1, intel TCS intervention (fast), start bit 40, length 8, Motorola unsigned, factor 0.39, % TCS intervention (slow), start bit 32, length 8, Motorola unsigned, factor 0.39, % ABS intervention, start bit 2, length 1, intel.

Yep, i'd be inclined to agree it's easiest to just hard wire it and that's what i've ended up doing . shame that a firmware update for the decoder box doesn't seem to exist. PCCMplus must have one ? The can id's you have are for the drive can bus , though some overlap must occur it's the comfort can bus that handles the Radio , aircon and gauge cluster. Hopefully attached is a list of can id's for the comfort can can bus on my 04 boxster S. The important i'd as far as i've found is at address 0x000, this is the id for the ignition switch and lights on . it's it's 3 bytes long and when the key is inserted the first byte goes from 00 to 01 and when ignition is on it goes from 01 to 03 . The second byte is lights on and goes from 00 to 64 . With time it would be possible to work out all the other id's. ID DLC Data Period Count Comment 000 3 01 00 00 100 1108 101 8 00 00 00 00 00 00 00 2F 102 1107 103 8 00 E0 00 E0 00 20 00 A0 102 1107 105 8 00 00 60 00 42 00 80 00 103 1107 107 6 01 00 80 00 00 00 999 111 111 2 C0 00 100 1106 2C1 4 00 20 26 55 1004 111 301 6 01 00 53 71 71 16 1000 111 303 8 80 72 00 30 12 78 65 CD 104 1107 304 5 34 53 46 60 76 999 111 305 6 00 00 00 00 00 00 1000 111 306 5 17 3A 35 98 0A 1000 111 316 6 1F 3F 3F 7F 0F 1F 830 60 400 4 01 02 02 FF 276 407 401 4 02 12 02 FF 280 407 402 4 00 12 02 FF 261 407 580 8 05 00 19 01 00 81 00 00 498 16 608 8 A3 00 00 00 00 00 00 00 999 387 618 8 A1 01 00 00 00 00 00 00 1000 387 in the table above id 0x000 shows key in ignition but not on and no lights 0x000 3 03 64 00 would be ignition on lights on. I never tried an engine running log.

i have a PCCM plus in mine, fitted it myself just following the supplied instructions. Cant remember if its hard wired or not I can pull it out at the weekend and take a look