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Old 28th June 2020, 15:26   #11
SD1too
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Originally Posted by goltho View Post
... why T4 was reporting cruise control as believing the brakes are on permanently.
Dougie; I recall from other threads that the brake pedal switch works on an electromagnetic principle. Is it possible that yours needs adjusting? You could place a multimeter across pins 2 & 4 and check that the switch operates correctly.

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Old 28th June 2020, 15:51   #12
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It appears to me as if C0775-3 needs to be connected to both the EAT ECU C0932-43 and the cruise relay C0895-6 ...
Dougie, have you checked that you have made BOTH connections?

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Old 28th June 2020, 15:54   #13
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Dougie; I recall from other threads that the brake pedal switch works on an electromagnetic principle. Is it possible that yours needs adjusting? You could place a multimeter across pins 2 & 4 and check that the switch operates correctly.

Simon
It's a hall effect switch Simon not a magnetic reed switch, and the automatic models with cruise have a two pole switch, pole 1 connects to the LSM for the brake lights, and pole 2 to the cruise ECU.
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Old 28th June 2020, 16:03   #14
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• The green/red (GR) wire from the brake switch pin 3 (C0775-3) is connected to the electronic auto transmission (EAT) pin 43 (C0932-43) ... It currently functions exactly the same as the wire from C0775-4 which controls the brakes lights i.e. power appears when the brake pedal is depressed.
According to your wiring diagrams this appears to be incorrect. Your diagram shows the brake pedal switch making pins 1 & 3 (sending +12v to two ECUs) but pins 2 & 4 sends an earth to the LSM, ABS ECU, cruise "relay" and cruise ECU, i.e. not exactly the same function.
Quote:
• Whilst T4 confirms the brake lights functioning correctly from C0775-4, it however reports the brakes being permanently on based on C0775-3. This is despite both pins C0775-3 and -4 behaving identically. This alone appears to be preventing cruise from working.
This suggests that there may be a problem with your brake pedal switch.
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• Pin 6 on the cruise control relay (C0895-6) requires to be connected to C0775-3; in the absence of header C0285 ...
I can't find C0285. Do you mean C0288?

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Old 28th June 2020, 16:03   #15
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Dougie, take a look HERE

Brian
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Old 28th June 2020, 16:08   #16
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It's a hall effect switch Simon ...
A Hall effect switch is an electromagnetic switch Brian.
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... the automatic models with cruise have a two pole switch, pole 1 connects to the LSM for the brake lights, and pole 2 to the cruise ECU.
Why does my RAVE wiring diagram show both the LSM and cruise ECU being connected to terminal 4 (which makes to terminal 2)?

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Old 28th June 2020, 16:13   #17
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I can't find C0285. Do you mean C0288?

Simon
Does this help Simon, Dougie is referring to header 0285, I've highlighted it for you, it's just below the picture of the double pole switch

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Old 28th June 2020, 16:14   #18
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A Hall effect switch is an electromagnetic switch Brian.

Why does my RAVE wiring diagram show both the LSM and cruise ECU being connected to terminal 4 (which makes to terminal 2)?

Simon
Simon, is yours a KV6?

Dougie.
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Old 28th June 2020, 16:16   #19
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Simon, is yours a KV6?

Dougie.
Yes, and it has cruise!

Simon
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Old 28th June 2020, 16:18   #20
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A Hall effect switch is an electromagnetic switch Brian.

Why does my RAVE wiring diagram show both the LSM and cruise ECU being connected to terminal 4 (which makes to terminal 2)?

Simon
I don't have any idea Simon, which version of RAVE do you have? there are at least five different revisions.

The diagram I'm looking at currently are RCL 0310 ENG Circuit Diagrams R.H.D.

I'm fairly confident Dougie has the incorrect switch fitted to his car, it has been seen on a few occasions now where people have retrofitted cruise.
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