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Electical Question re: Pin 18 on Cab Relay - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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YOUR RESEARCHElectical Question re: Pin 18 on Cab Relay - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Check electrical diagrams in the back of a bentley manual

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Suggestion
Check the electrical diagrams in the back of a Bentley manual to verify.
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Electical Question re: Pin 18 on Cab Relay - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Leading evidence: 'Check electrical diagrams in the back of a bentley manual' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check electrical diagrams in the back of a bentley manual' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Run from pin #1 at the radio

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Suggestion · Original poster
A wire was run from pin #1 at the radio to pin #18 of the dual relay for the cabriolet top.
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Electical Question re: Pin 18 on Cab Relay - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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Check electrical diagrams in the back of a bentley manual

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion
Check the electrical diagrams in the back of a Bentley manual to verify.
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Electical Question re: Pin 18 on Cab Relay - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Run from pin #1 at the radio

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion · Original poster
A wire was run from pin #1 at the radio to pin #18 of the dual relay for the cabriolet top.
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Electical Question re: Pin 18 on Cab Relay - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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POST 1 / ORIGINAL POSTEROriginal post

I just wired my Becker radio so the variable volume function would work. A wire was run from pin #1 at the radio to pin #18 of the dual relay for the cabriolet top. The mod has been well documented and I now have automatic increases in volume as the car goes faster. My question is kinda techical: What is the signal pin #18 emits ? I want to install a CDR in my 914 and would like to figure a way to duplicate the signal. The first thought was to consider the Tach signal. Any eletrical geru's out there ? Thanks, Jim

POST 2Original post

I might be wrong, but pin #18 in the top relay does not emit any signal. Pin 18 in the relay is a cut off so that when it receives a signal it cuts power to the convertible top motors to prevent damage. Therefore, I would assume it gets the signal from the ECU for the speedometer. Wouldn't make sense for it to come from the Tachometer b/c you can rev the engine as much as you want when stationary and still raise/lower the top. Check the electrical diagrams in the back of a Bentley manual to verify. Good luck

POST 3 / ORIGINAL POSTEROriginal post

Good point, I had it backwards. My question should be what type of signal does pin 18 receive from ?????? My thought was to install a Becker in my 914; if I knew the type of signal controls the variable volume, I might be able to make a facsimilie ---with the help of someone with a lot more knowledge than myself.

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