Electrical Woes

[Oilydwarf]

Morning all,

Hoping that someone can steer me in the right direction to help keep my 2001 R1150GS on the road. Owned from new, 70K and until recently been as good as gold. Been though many of the threads but not found one that covers exactly these issues, apologies if I have missed something.

Problems started with the hazard lights switching themselves on at random. Would not turn off with the cancel switch the RH bar so I had to remove the flasher unit which means riding without any indicators. Not legal and not ideal in traffic but could still ride.

More recently the starting became erratic. Sometimes the starter would crank the engine, more often than not absolutely nothing. Ran a lead direct from the battery to the relay on the starter motor and it cranks up fine so the starter motor is good. The black lead that feeds the relay on the starter motor is however showing +12V all the time the ignition is on and not just when I hit the starter button. There is continuity between pin 87 in the fuse board and the lead to the starter relay, but I still get 12v on the lead even with the starter relay in the fusebox removed! Found out last night that if I disconnect the lead to the relay on the starter motor relay I lose all my lights - front, rear, the whole lot! Plug the lead back in and the lights come back.

Have also noticed that the side stand switch causes the engine to cut out when the side stand is mid way between down and up, managed to live with that by flicking it up quickly and giving it revs so the engine has the momentum to get it through the dead spot. Might a faulty side stand switch cause these problems?

All the dash lights work fine, oil, battery, gear selector indicator so no probs up there.

Lets be honest, the wiring on these is not simple even for someone who is technically literate so I would appreciate advice from anyone who has had a similar experience. Keen to try and home in on the culprit parts before I start spending time and money replacing everything in the hope that they cure the problems.

I love this bike (even though I have a couple of newer GS's) and want to keep it on the road for as long as I can. Any help much appreciated.

 

[Riceburner]

One thing to check, albeit as a single point of failure in what sounds like a list, would be the wiring looms at the headstock. These often fail at higher mileage due to the constant movement of the steering wearing out, and eventually breaking, the copper inside the wiring at that point. This is made far worse if the looms are cable-tied tightly to the headstock (which is how they were supplied by the factory). Even if the looms have been freed from the cable-ties, they are still weak and prone to failure. I had the failure happen at around 80k miles, after I'd freed the looms at 2k miles. (On my 3rd Rockster)

Replacement ignition loom isn't that expensive.

 

[Oilydwarf]

Thanks for the suggestion. I presume I'll need to remove the looms and carry out a continuity test between the connector block pins and the other end of each wire in the switch gear/ignition etc. The lights issue sounds like it might be some sort of earth issue, any idea where the earth points are for the loom, particularly lights? Seen some posts about water getting into the loom and corroding the crimped earth connections but I can't see where they are from my wiring diagram. Your help is much appreciated!

 

[KMD]

@Ian J Hartley may be able to assist here. He is excellent with electrics.

 

[Oilydwarf]

Thanks for the suggestion. New to site, can't se how to DM Ian, do I need to be a subscriber? If so I'll try and work out how to subscribe!

 

[Steptoe]

The main loom from the instrument panel has a large multi earth point inside.
The loom sheath isn’t sealed at each end so water gets inside, and sod’s law, the earth is on the bend in the loom, so any water entering sits just where the earth is.
After a few years the earths turn to a green mush, verdigris..
this may not be your main problem but could be causing some, plus it’s easy to check.

 

[Ian J Hartley]

Problems started with the hazard lights switching themselves on at random. Would not turn off with the cancel switch the RH bar so I had to remove the flasher unit which means riding without any indicators. Not legal and not ideal in traffic but could still ride.

You may have just a faulty flasher relay, but as you have it disconnected try doing some continuity checks at the connector.

You will see from the wiring diagram, that all the hazard, left indicator, right indicator and cancel switches do is provide an earth to the flasher relay. The power on pin 1 green/blue is for the indicators to work whilst the bike ignition is on, The battery power on pin 2 is to keep the hazards on when the ignition is off, provided you have pressed the hazard button first.

 

[Ian J Hartley]

More recently the starting became erratic. Sometimes the starter would crank the engine, more often than not absolutely nothing. Ran a lead direct from the battery to the relay on the starter motor and it cranks up fine so the starter motor is good. The black lead that feeds the relay on the starter motor is however showing +12V all the time the ignition is on and not just when I hit the starter button. There is continuity between pin 87 in the fuse board and the lead to the starter relay, but I still get 12v on the lead even with the starter relay in the fusebox removed! Found out last night that if I disconnect the lead to the relay on the starter motor relay I lose all my lights - front, rear, the whole lot! Plug the lead back in and the lights come back.

Too complicated to explain to you how the load relief relay and the starter solenoid work electrically, but what you described, is exactly how the system works, so all good there.

However, The fact that your starting is erratic could point to either a faulty kill switch, starter button or starter relay (big yellow one in fuse box). This may also be linked to your side stand switch, which sounds faulty to me.

There are a couple of things you can try.
1. Pull in the clutch before you press the start button, this provides an alternate path for the starter relay earth the other earth path is via the side stand switch and gear box.
2. Disconnect the black wire to the starter solenoid. Put your finger on the starter relay and press the starter button. You should be able to feel the relay operate.
3. Replace the starter relay with a standard type A relay rated at 30Amps. The bike will only start with clutch lever pulled in.

I’m sure I did a write up on how to check the start circuit form the start relay. I’ll see if I can find it

 

[Ian J Hartley]

Starter Relay checks

To Start Bike with faulty relay removed.

1. Ignition on
2. Neutral
3. Momentary jump across 30 (Battery) to 87 (Starter Solenoid)

To Check Start button

1. Ignition On
2. Neutral
3. Kill switch centred
4. +12 volts should be present at 85 (Start Switch) when pressed.

To Check clutch switch

1. Resistance check no power to bike
2. Measure between 86 (clutch switch ) and earth
3. Press clutch lever the value should go from open to short circuit.

Relay can be replaced with standard type A relay preferably with a rating greater than 30 amps. Clutch will need to be operated to start bike.

 

[Oilydwarf]

Apologies for the late reply, only just the time to work on the bike. Thanks Ian, your advice was on the money and the pictures invaluable. Traced the fault to a broken starter motor switch in the RH switch cluster. Had sourced one a while ago so unsoldered the old one and soldered a new one in. Bingo, bike back to normal! Still got the erratic emergency flashers to sort out but I suspect that's another switch failing to the on position rather than the off position. Amazes me how right BMW got it with the 1150, in many respects I prefer it to my newer GS's.