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RPM Signal for Shift Light

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Old 08-02-2017 | 10:51 PM
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Default RPM Signal for Shift Light

Hi All

Tried a search no luck.

I'd like to install a sequential shift light in a 987.2 Cayman R but not sure how to tap into the RPM signal. Any thoughts?

Thanks

Brian
Old 08-03-2017 | 07:03 AM
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Originally Posted by bdf
Hi All

Tried a search no luck.

I'd like to install a sequential shift light in a 987.2 Cayman R but not sure how to tap into the RPM signal. Any thoughts?

Thanks

Brian
Should be one in the OBD connector.
Old 08-08-2017 | 10:02 AM
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Default OBD

Here is the OBD wiring for a Boxster
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Old 07-11-2020 | 01:58 AM
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Default RPM signal tap for 987.2

Hi,

I have the same question. Trying to find out where the correct wire is to tap at the ECU to get the RPM signal for a shift light in a 987.2.

Did you ever find out?

OBD is not possible on the 987.2
Old 12-13-2020 | 12:23 PM
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I searched a ton of threads but could not find anything for the .2 cars. Peter Krause was nice enough to give me a detailed response in a facebook group, so I thought I'd add it to Rennlist for the next person who comes searching for the same answers:


For 987.1 you can tap into the OBD port wires, lookup Boxster and 997 installs. The OBD port is clipped in with 3 clips, squeeze those and push it up into the dash to release it. For 987.2 cars, that wire is no longer there, you have to tap into the DME harness back in the trunk. Upper connector on the DME, tap one of the wires going to pin 78, 79, or 80 will work. You will need to unwrap the cloth tape quite a bit to get there.
Old 01-02-2021 | 08:44 PM
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Originally Posted by Rmag911
I searched a ton of threads but could not find anything for the .2 cars. Peter Krause was nice enough to give me a detailed response in a facebook group, so I thought I'd add it to Rennlist for the next person who comes searching for the same answers:
Update: I installed my Cartek Club shift lights. Here is the wiring diagram for the DME:



The trick here is that the colors for pins 78-80 are used by TWO different wires in the B slot of the DME (the top slot). I attached the shift light to a white/red wire in the bundle going into the DME and nothing happened. Took a while to figure out that there was a second White/Red wire on the other side of the wire bundle.

Also, any of the ignition cylinder wires will work, including the ones going into pins 54-56.
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Old 03-23-2021 | 11:23 AM
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Just if anyone start googling like me and finds no info on an rpm signal on a 981 Cayman:

I just fitted a shift light to my Cayman GT4 Clubsport (981), Ecliptech Shift P2.

You can use the same cable as mentioned above for RPM, 78, 79 of 80 on the big DME connector in the trunk. Colors are different on a GT4 CS: 78 GRN/BLK 79 GRN/WHT 80 GRN/GRY
Old 02-19-2022 | 03:15 AM
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Originally Posted by Liftlargesarge
Hi,

I have the same question. Trying to find out where the correct wire is to tap at the ECU to get the RPM signal for a shift light in a 987.2.

Did you ever find out?

OBD is not possible on the 987.2
Is RPM not accessible via the OBD on a Cayman 987.2?
Old 02-19-2022 | 09:27 AM
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Originally Posted by GroupJ
Is RPM not accessible via the OBD on a Cayman 987.2?
No
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Old 02-22-2022 | 12:11 AM
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You really don’t want to use the OBD2 for a critical signal like RPM as the update rate is so sllow.
Old 02-22-2022 | 03:21 PM
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Thanks for input
Old 06-05-2022 | 05:33 AM
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I used Cartech OBD version on my 987.2 and it works great
Old 11-19-2022 | 08:10 PM
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So when does the shift light come on? 7K rpm??? I'd like a light to alert me when I am at say 6.5K rpm Wondering if there is something that can attached to a plug wire that'd function as an rpm reader and then could have a light somewhere that'd come on to tell you to shift.
Old 11-21-2022 | 04:05 AM
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The Cartech unit is programmable - it has 3 colors green, blue and red I recall. I programmed mine to start at 4k - green , 5K- blue , 7K - red. On the track I try to always have the lights on (never drop below 4k) and shift at 7K.
Old 11-21-2022 | 09:57 AM
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Originally Posted by GroupJ
The Cartech unit is programmable - it has 3 colors green, blue and red I recall. I programmed mine to start at 4k - green , 5K- blue , 7K - red. On the track I try to always have the lights on (never drop below 4k) and shift at 7K.
Would recommend 4500 Green, 6500 blue, 7000 red.

Most folks try to game the lights. Just shift when the light comes on.


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