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TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: mitchapalooza88 on July 01, 2020, 11:19:50 PM

Title: No Power to Starter Relay
Post by: mitchapalooza88 on July 01, 2020, 11:19:50 PM
Hello all, I bet there’s a post somewhere for this one but I can’t find my exact answer.
I’m currently getting no power to the starter relay.

-I pulled the starter relay off and bench tested it and it’s switching correctly at 12V
-Handlebar starter button  is working correctly
- Gear selector position is working correctly. Currently in neutral
- kickstand kill switch is working correctly
- load shedding relay is clicking when starter is pressed
- I jumped the two large terminals on the starter relay and the starter turns over

One other oddity I am noticing is my keyless fob isn’t arming and unarming the bike but maybe my fob battery is dead. I tried unplugging the alarm system but that left no change. Maybe I have the alarm system connections wrong on the battery terminals?

Any ideas would help!
Title: Re: No Power to Starter Relay
Post by: mitchapalooza88 on July 01, 2020, 11:22:06 PM
Also the fuel pump does run when I press the start button as it usually does.
Title: Re: No Power to Starter Relay
Post by: Laitch on July 01, 2020, 11:25:03 PM
The K75 doesn't have a side stand switch as OEM equipment. Did you add one? What's the resting battery voltage? Have you checked your positive and negative battery connections for tightness?
Title: Re: No Power to Starter Relay
Post by: mitchapalooza88 on July 01, 2020, 11:43:38 PM
The K75 doesn't have a side stand switch as OEM equipment. Did you add one? What's the resting battery voltage? Have you checked your positive and negative battery connections for tightness?

Battery voltage is 12.6 v I also hooked another battery in parallel as a dummy test. Connections are good.

Also all the fuses in the fuse box are intact with no corrosion on the spades.
Title: Re: No Power to Starter Relay
Post by: Laitch on July 01, 2020, 11:53:59 PM
What about the side stand switch; did you install that? Is the alarm aftermarket or stock?
Title: Re: No Power to Starter Relay
Post by: mitchapalooza88 on July 02, 2020, 12:01:50 AM
What about the side stand switch; did you install that? Is the alarm aftermarket or stock?

I guess no stand switch after all, I was pressing the lever behind the stand and I thought I was hearing the clicking of a switch but it was just the clutch pull.

The alarm is a Genuine BMW alarm system
Title: Re: No Power to Starter Relay
Post by: daveson on July 02, 2020, 12:21:43 AM
At the starter relay, either you're not getting power at 86, or you're not getting earth to 85, while the start button is pressed.
Title: Re: No Power to Starter Relay
Post by: Laitch on July 02, 2020, 12:58:25 AM
A poor connection in the alarm wiring could be disabling the starter. Have a look at this (https://www.motobrick.com/index.php/topic,9008.msg71239.html#msg71239).
Title: Re: No Power to Starter Relay
Post by: The Mighty Gryphon on July 02, 2020, 07:48:14 AM
I'm guessing the problem is in the alarm system.  One of it's functions is to immobilize the bike.  You wouldn't be the first person to have a problem with that alarm.  Do a search on alarm system and it will show you some of the problems others have had.
Title: Re: No Power to Starter Relay
Post by: mitchapalooza88 on July 02, 2020, 09:33:21 AM
PROBLEM SOLVED

Thanks guys. The alarm schematic was exactly what I needed. When I reattached the alarm system I had all the wires on ground so the alarm system wasn’t receiving power.

I couldn’t remember if it prevented start up or not every time I tried starting the bike armed I was too busy cleaning the pee stain in my pants from the abnormally loud horn going off
Title: Re: No Power to Starter Relay
Post by: mitchapalooza88 on July 02, 2020, 09:37:56 AM
Love this thing. I’m lucky to have a super original low mile (10k) bike, plus I got it for $500
Title: Re: No Power to Starter Relay
Post by: Laitch on July 02, 2020, 09:49:08 AM
I’m lucky to have a super original low mile (10k) bike, plus I got it for $500
Don't tempt fate.  :laughing4-giggles: