Hitchcocks Forum

I have had this problem for a while. I know that it is down to the lights somehow earthing through one another, but I can't seem to fix it. Any ideas? One idea I had was to try to use diodes to stop the "reverse" current?

Hello JON R (great names !!)----- before going all "tecky" on us with diodes etc, have a look closer to home and do a thorough check on the earthing of all the items concerned. ie take them off---remove any paint etc to ensure a proper meta-to-metal contact. Also pull out and replace the various bullet connectors in the wiring. Finally, just run your fingers/hand along the loom to ensure no short circuits---crossed wiring etc. Those symptoms are a clasic "High resistance earth" symptom. The current isn't "reversed"---just doing what it does best---finding the path of least resistance. Take a look in your tool kit---in the very bottom tray---you'll need }---- Patience (UNF) & Perseverance (metric).

............and make up a temporary earth lead(s) direct from battery and try earthing all fittings. If you put a volt meter into this circuit then reading should be zero when light etc is switched on - anything more indicates a resistance or poor earth through normal earth route. Rear light unit earthing is always suspect, but forks/nacelle to frame resistance is not unknown.

John, forget the diode bit, it is an earthing problem

Yes, I KNOW about the earth problem, and you are right, the diode bit is a bit desperate. It's just that I have tried cleaning up the connections, even running a cable direct from the rear lights to the -ve battery terminal.

Hi John. looking at the wiring diagram it appears you have a leakage across the inside of the rear brake light switch...possibly water and salt. Remove the stop light switch and thoroughly clean in soapy water and dry off with meths (or isopropanol). As a pre-test, when you have it removed (or in situ) with all wiring connections removed, check with a meter to see if you have a lowish OHMs reading across the two terminals. If you have and cannot clean up the short you will need a new brake switch..let me know what happens after this procedure please....Les....PS I could tell you where to fit a single diode to stop the problem but it should not be required. It will be on the red/white whire that feeds the stop light switch.

As another test John: Remove the wires from the rear brake light switch and operate the indicators and also operate the stop light switch by shorting the connections manually with a short length of wire. Both systems should operate normally and prove the switch is faulty. (or not)

I have the opposite problem on my Bullet 350 from 2002. When I brake - either by handbrake or footbrake - the indacators stop blinking (or get so week so other trafficants can not see them). I have tried all kinds og "earthing" solutions, no one helps. Even have used the method with a wire from battery earth to stoplight, backlight and so on, nothing helps. (been so since I bought it two years ago) (The headbeam get the electricity directly from alternator.). Any tips or ideas what to do? Svante in Sweden

Hi Svante. You problem is not earth related. It is more likely to be a high resistance on the + supply to the flasher unit. The wire is the red/white and you should check and clean the connectors in the headlamp. There is a possibilty that there is a short to earth, acting as a heavy load when you operate the stop lights. This could be within either of the switches (more likely the rear stop light foot switch)OR in the wiring OR in the rear light cluster assembly.....try running a wire directly to the flasher unit from the + side of the battery connect this onto the red/white wire terminal of the switch. If things improve, then you have a high resistance in your wiring ....IF not...the stop light switch is shorting to earth slightly somewhere.

Please note: the red/white wire supplies the flasher unit + rear stop light switch....and you have another red/white wire that supplies the front stop light circuit + coil. Both are joined on a connector in the headlight unbit. However directly feeding the flasher unit to bypass its red/wire feed will prove whether the fault is a High Resistance connection or if it remains, there is a heavy load occuring due to a short down to earth on the sop lamp circuit.