997TT MK.1 PCM 3 conversion DONE :)
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Those solutions look really good, frankly. And it doesn't seem clear that you get all that pcm info on the improvised unit. With a new pioneer or alpine you could get a porsche faceplate and easily also have a rear view camera. I have the pcm3 now, but not sure I would drop it into a .1. Of course depends on the cost. How much is it?
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so boyz, let's do some updates about a/c unit.
we all have two ways to buy this - buy new one or buy used at ebay.
used one is a challenge to try your luck...
because
on 997.1 a/c compressor is switched on/off from DME with analog (-) signal thru relay, and theres "status" wire from this relay to a/c unit.
on 997.2 a/c compressor is switched on/off from a/c unit with PWM (+) signal with single straight-connected-to-compressor wire.
ONLY EXEPT here is turbo 09. which have old principle but new fachia.
if you buy used you just can't guess from what car it is, because number on it and catalogue number have nothing similar.
SO.
you are lucky one if bought used turbo 09 a/c unit, or new one. your headache will be in one thing - 997.1 don't have evaporator temp sensor, so you will need to install this one with two wires, plug and cut hole with dremel tool, OR "fool" a/c unit with resistor.
in other case you will need help of VERY GOOD electrician.
you will need to cut "status" wire from a/c relay, not touching other wires.
MAKE PWM-to-analog schematic and connect "status" wire to input
and install second a/c relay, actuated from output of schematic.
or convert wiring of original a/c relay to get it actuated from schematic, and fool dme with second relay connected to two freed wires. that is up to electrician.
next fake a/c unit or install evap temp sensor.
and code/erase errors
all work
we all have two ways to buy this - buy new one or buy used at ebay.
used one is a challenge to try your luck...
because
on 997.1 a/c compressor is switched on/off from DME with analog (-) signal thru relay, and theres "status" wire from this relay to a/c unit.
on 997.2 a/c compressor is switched on/off from a/c unit with PWM (+) signal with single straight-connected-to-compressor wire.
ONLY EXEPT here is turbo 09. which have old principle but new fachia.
if you buy used you just can't guess from what car it is, because number on it and catalogue number have nothing similar.
SO.
you are lucky one if bought used turbo 09 a/c unit, or new one. your headache will be in one thing - 997.1 don't have evaporator temp sensor, so you will need to install this one with two wires, plug and cut hole with dremel tool, OR "fool" a/c unit with resistor.
in other case you will need help of VERY GOOD electrician.
you will need to cut "status" wire from a/c relay, not touching other wires.
MAKE PWM-to-analog schematic and connect "status" wire to input
and install second a/c relay, actuated from output of schematic.
or convert wiring of original a/c relay to get it actuated from schematic, and fool dme with second relay connected to two freed wires. that is up to electrician.
next fake a/c unit or install evap temp sensor.
and code/erase errors
all work
Last edited by Serg124; May 13, 2014 at 01:34 PM.
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mmm.. boxter/cayman have a/c unit with 997 number and same wiring... so all units will work, but best fit is only one - from 997.1 tt '09
number is 99765321503FTC with seat heating, 99765320502FTC - without
number is 99765321503FTC with seat heating, 99765320502FTC - without
Last edited by Serg124; May 12, 2014 at 06:31 AM.
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Correct Rye! you can get more for your $ in an aftermarket system that the desginers built for sound unlike the OEM unit that is basically tossed in there.
Frankly if you are lucky this PCM 3 costs 2k and you still arent covered by warranties. for the 3k i think it will cost you can have a really nice system
Frankly if you are lucky this PCM 3 costs 2k and you still arent covered by warranties. for the 3k i think it will cost you can have a really nice system
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Correct Rye! you can get more for your $ in an aftermarket system that the desginers built for sound unlike the OEM unit that is basically tossed in there. Frankly if you are lucky this PCM 3 costs 2k and you still arent covered by warranties. for the 3k i think it will cost you can have a really nice system
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OK )))
if bought used turbo 09 a/c unit, or new one, your headache will be in one thing - 997.1 don't have evaporator temp sensor, so you will need to install this one with two wires, plug and cut hole with dremel tool, OR "fool" a/c unit with resistor.
if bought used turbo 09 a/c unit, or new one, your headache will be in one thing - 997.1 don't have evaporator temp sensor, so you will need to install this one with two wires, plug and cut hole with dremel tool, OR "fool" a/c unit with resistor.
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Thanks! So even with a 09 turbo ac unit we will still need to use a resistor.
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so boyz, let's do some updates about a/c unit.
we all have two ways to buy this - buy new one or buy used at ebay.
on 997.1 a/c compressor is switched on/off from DME with analog (-) signal thru relay, and theres "status" wire from this relay to a/c unit.
on 997.2 a/c compressor is switched on/off from a/c unit with PWM (+) signal with single straight-connected-to-compressor wire.
ONLY EXEPT here is turbo 09. which have old principle but new fachia.
if you buy used you just can't guess from what car it is, because number on it and catalogue number have nothing similar.
SO.
you are lucky one if bought used turbo 09 a/c unit, or new one. your headache will be in one thing - 997.1 don't have evaporator temp sensor, so you will need to install this one with two wires, plug and cut hole with dremel tool, OR "fool" a/c unit with resistor.
in other case you will need help of VERY GOOD electrician.
you will need to cut "status" wire from a/c relay, not touching other wires.
MAKE PWM-to-analog schematic and connect "status" wire to input
and install second a/c relay, actuated from output of schematic.
or convert wiring of original a/c relay to get it actuated from schematic, and fool dme with second relay connected to two freed wires. that is up to electrician.
next fake a/c unit or install evap temp sensor.
and code/erase errors
all work
we all have two ways to buy this - buy new one or buy used at ebay.
on 997.1 a/c compressor is switched on/off from DME with analog (-) signal thru relay, and theres "status" wire from this relay to a/c unit.
on 997.2 a/c compressor is switched on/off from a/c unit with PWM (+) signal with single straight-connected-to-compressor wire.
ONLY EXEPT here is turbo 09. which have old principle but new fachia.
if you buy used you just can't guess from what car it is, because number on it and catalogue number have nothing similar.
SO.
you are lucky one if bought used turbo 09 a/c unit, or new one. your headache will be in one thing - 997.1 don't have evaporator temp sensor, so you will need to install this one with two wires, plug and cut hole with dremel tool, OR "fool" a/c unit with resistor.
in other case you will need help of VERY GOOD electrician.
you will need to cut "status" wire from a/c relay, not touching other wires.
MAKE PWM-to-analog schematic and connect "status" wire to input
and install second a/c relay, actuated from output of schematic.
or convert wiring of original a/c relay to get it actuated from schematic, and fool dme with second relay connected to two freed wires. that is up to electrician.
next fake a/c unit or install evap temp sensor.
and code/erase errors
all work
thanks so far, great work! Some things are not clear to me.
1. NTC (evaporator) - Install a resistor to fool the CU Climatronic.
Install a Resistor from the CU (dme) Pin B16 --> Ground
(How many Ohms will fit?)
- There is already a wire on Pin PB16, old 997.1 CU wiring "Compressor Voltage".
(Can I leave this connection or should i remove this?)
2. Compressor Relay
The CU pin D14 should now drive the relay. I assume the, output of pin D14 is 12 volt aware and this output can drive a new installed 12 volt relay. This relay will switch the relay (Compressor Relay) pin A2 to ground.
Please reply. Thanks again.
K.
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I'm not one-two-three-four - only one-two-four 
resistor between b9 and b16
ohm... didnt write this down, sorry...
plugs or course should be re-pinned according wiring diagrams of 997.2, also there will be new plug for button strip. b16 move to d14 etc.
about relay - if using 997.1T'09 climate ecu - only re-pin ecu plugs, do not need to touch relay.
if other ecu version - need to make pwm-to-analog converter schematic as described.
resistor between b9 and b16
ohm... didnt write this down, sorry...
plugs or course should be re-pinned according wiring diagrams of 997.2, also there will be new plug for button strip. b16 move to d14 etc.
about relay - if using 997.1T'09 climate ecu - only re-pin ecu plugs, do not need to touch relay.
if other ecu version - need to make pwm-to-analog converter schematic as described.
