Neutral light problem returns

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ptjenkins65
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Neutral light problem returns

Postby ptjenkins65 » Wed Nov 29, 2017 1:29 pm

Hello all.

Earlier in the year, you helped me when my r45 neutral light would not come on and thus the engine would not turn over.
It transpired I had a faulty gearbox neutral pressure switch. I replaced the gearbox neutral switch after bypassing the switch for a while with a wire from the brown/ black to the battery negative.
I went to use it yesterday and the same problem has occurred.
Again I have connected the brown/ black wire direct to the battery negative via an auxiliary wire and the light lights and the bike turns over. Does this mean the gearbox pressure switch is faulty again or could there be another reason?

Regards Pete
1998 r850r
1979 r45
1974 r60/6
Still learning

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Galactic Greyhound
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Re: Neutral light problem returns

Postby Galactic Greyhound » Wed Nov 29, 2017 1:55 pm

Hi Pete,

The first thing is to ensure that you have the correct replacement Neutral Switch for your R45.
The Neutral Switches come in different types so you must get the correct item.

To ensure that you have the correct part, put the last 7 digits of your VIN into the RealOEM website 'Serial Number' box and hit 'Search': http://www.realoem.com/bmw/enUS/select
The actual manufacturing year and build of your R45 will then be shown at the bottom of the page.
Select the 'Browse Parts' box.
Select 'Manual Transmission'.
Select 'Gearbox Cover, Gasket & Various Bolts'.
Look for the Neutral Switch shown in the diagram and its Designation Number (13?)
Look also for the Gasket Ring (Washer) in the diagram and its Designation Number (12?)
Look in the Parts List below the diagram for these items and obtain the BMW Part Numbers for the TWO items.

Check that your Neutral Switch is the correct part AND that the Gasket Ring is also the correct part.

If in doubt, go to the Motorworks website: https://www.motorworks.co.uk/vlive/Home/index.php
Put these BMW Part Numbers into the Motorworks Search box at the top of the page WITHOUT any spaces.
Check the Motorworks Part Numbers and Description fit the items you have.

NOTE: It is MOST important that the correct Gasket Ring is fitted to the Neutral Switch otherwise the switch may not operate correctly.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" onclick="window.open(this.href);return false; - It works!

ptjenkins65
Club Member 12
Posts: 41
Joined: Thu Jun 08, 2017 7:49 pm
Country of Residence: United Kingdom
Location: London

Re: Neutral light problem returns

Postby ptjenkins65 » Wed Nov 29, 2017 6:38 pm

Hello Ced. The numbers all match up with what I bought. I have contacted Motorworks and they are replacing the switch and washer under warranty.
Back under the bike for me.
Regards Pete
1998 r850r
1979 r45
1974 r60/6
Still learning

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Galactic Greyhound
Moderator/Club Member
Posts: 7819
Joined: Sat Aug 28, 2010 11:26 pm
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Location: Dumfries

Re: Neutral light problem returns

Postby Galactic Greyhound » Wed Nov 29, 2017 7:32 pm

Good for Motorworks!

Bear in mind that there could be another cause for the Neutral Light not working in that the Neutral Switch Brown earth wire is not making a secure contact to the main frame earth so one side of the switch is not being earth-connected.

You can prove if this is the case by TOUCHING a wire from the Battery Negative (Earth) terminal to the Neutral Switch BROWN wire terminal (with the wire still connected to the switch) while the bike is sitting in Neutral with the Ignition On.
If the earth to the switch is faulty the Neutral Light will now illuminate.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" onclick="window.open(this.href);return false; - It works!

ptjenkins65
Club Member 12
Posts: 41
Joined: Thu Jun 08, 2017 7:49 pm
Country of Residence: United Kingdom
Location: London

Re: Neutral light problem returns

Postby ptjenkins65 » Thu Nov 30, 2017 10:19 am

Hi Ced. The light did no come when I touched a wire from the connected brown wire at the switch to the negative battery terminal.
Faulty switch?
Regards Pete
1998 r850r
1979 r45
1974 r60/6
Still learning

User avatar
Galactic Greyhound
Moderator/Club Member
Posts: 7819
Joined: Sat Aug 28, 2010 11:26 pm
Country of Residence: Scotland
Location: Dumfries

Re: Neutral light problem returns

Postby Galactic Greyhound » Thu Nov 30, 2017 11:16 am

Hi Pete,

Looks like it is a faulty switch or the operating mechanism for the switch in the gearbox is faulty.

You can confirm that your earth wire test is OK as follows:

With an earth wire connected to the Battery Negative (earth) terminal, the gearbox in Neutral and the Ignition On:

1. Touch the other end of the earth wire to the Neutral Switch Brown/Black wire terminal - the Neutral Light should illuminate.

2. Touch the other end of the earth wire to the Neutral Switch Brown wire terminal - if the Neutral Light now illuminates the earth to the Neutral Switch is faulty.

If the Neutral Light still does not illuminate then the Neutral Switch OR the gearbox operating mechanism is faulty.

Try selecting another gear and then go back into Neutral to see if the Neutral Light comes on - some boxes will not go into Neutral properly unless the gears are spinning - can you start the engine and get the rear wheel turning then select Neutral?

If you think the switch is faulty, remove it and test it for correct operation on the bench.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" onclick="window.open(this.href);return false; - It works!

ptjenkins65
Club Member 12
Posts: 41
Joined: Thu Jun 08, 2017 7:49 pm
Country of Residence: United Kingdom
Location: London

Re: Neutral light problem returns

Postby ptjenkins65 » Wed Dec 06, 2017 9:01 am

Hi. I have done the test below with these results.
With an earth wire connected to the Battery Negative (earth) terminal, the gearbox in Neutral and the Ignition On:

1. Touch the other end of the earth wire to the Neutral Switch Brown/Black wire terminal - the Neutral Light should illuminate.Yes it does

2. Touch the other end of the earth wire to the Neutral Switch Brown wire terminal - if the Neutral Light now illuminates the earth to the Neutral Switch is faulty.It does not illuminate.

If the Neutral Light still does not illuminate then the Neutral Switch OR the gearbox operating mechanism is faulty.

I now have the old switch out and the new one has arrived.
What is the bench test that I should do?
Regards Pete
1998 r850r
1979 r45
1974 r60/6
Still learning

User avatar
Galactic Greyhound
Moderator/Club Member
Posts: 7819
Joined: Sat Aug 28, 2010 11:26 pm
Country of Residence: Scotland
Location: Dumfries

Re: Neutral light problem returns

Postby Galactic Greyhound » Wed Dec 06, 2017 12:19 pm

Hi Pete,

From the last test results, the problem would appear to be with the Neutral Switch or its operating mechanism in the Gearbox.

To bench test the Neutral Switch using your Test Lamp, connect one lead of your Test Lamp to the Battery POSITIVE terminal and one terminal of the Neutral Switch to the Battery NEGATIVE (earth) terminal.

Check your Test Lamp is working by touching it to the Battery NEGATIVE (earth) terminal - it should light fully.

Now touch your Test Lamp to the Neutral Switch other terminal.

What should happen depends on whether the switch is a Normally Closed (NC) or a Normally Open (NO) type.

NC Type: The Test Lamp should light fully.
When the switch is operated the Test Lamp should NOT light.

NO Type: The Test Lamp should NOT light.
When the switch is operated the Test Lamp should light fully.

You should test the OLD and the NEW Neutral Switches as above to see if they are both working OK or not.

If both give the same results, then it is likely that the wrong washer has been used or the gearbox operating mechanism is faulty.

If the gearbox mechanism is suspected, try refitting the switch and repeatedly come out of and go into Neutral while the rear wheel is rotating.
This will often 'encourage' the mechanism to work properly.
If your R45 has been off the road in a shed for a few years it is not surprising that some things may be a bit 'sticky' - these problems should likely clear once you get the bike running and used properly again as the engine and gearbox oil gets things lubricated.

When fitting the Neutral Switch to the Gearbox, the correct washer (gasket ring) MUST be used.

Incidentally, you don't have to use the bike battery to test individual components for continuity using your Test Lamp - a 9 volt dry battery such as used in Smoke Alarms and the like will do the job as well keeping you in the warm and dry! In this case a 5 Watt bulb is about the highest wattage you want in your Test Lamp to avoid drawing too much current from the dry battery.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" onclick="window.open(this.href);return false; - It works!

ptjenkins65
Club Member 12
Posts: 41
Joined: Thu Jun 08, 2017 7:49 pm
Country of Residence: United Kingdom
Location: London

Re: Neutral light problem returns

Postby ptjenkins65 » Thu Dec 07, 2017 8:39 am

Hi All. I did what Ced suggested and the new neutral passed the test, it is a NC type and the old failed.
Ive fitted the new and all now seems to be working as it should.
Thanks again for the help.
Regards Pete
1998 r850r
1979 r45
1974 r60/6
Still learning

User avatar
Galactic Greyhound
Moderator/Club Member
Posts: 7819
Joined: Sat Aug 28, 2010 11:26 pm
Country of Residence: Scotland
Location: Dumfries

Re: Neutral light problem returns

Postby Galactic Greyhound » Thu Dec 07, 2017 9:58 am

Hi Pete,

Glad you got it sorted! :smile:
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" onclick="window.open(this.href);return false; - It works!


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