Yamaha TRX850 Enthusiasts Forum

Hello, I am replacing my ignition switch with a remote control switch. While checking the plug where the ignition switch plugs into the loom (trying to check which wires need to be active) I managed to trip something and now have no power to the dash, it will not start. All the fuses are fine, have swapped them out with replacements, but no go.
I heard something like a relay click. My original switch is hard to operate and would need replacing.
I have disconnected the battery and reconnected, but did not help.
Have looked at wiring diagram, realises that only two of the wires need to be active, I think.
Any help would be appreciated.

Hiya Dave, someone will hopefully give you a more comprehensive answer! Have you checked through all the wiring and connections, if you've accidentally jumped a cable you might have overloaded a wire/connector rather than a fuse. Also check all your connections are good, bad earths can be the route of all kinds of chaos. Have you put a gauge across the battery terminals to check the battery is actually ok?

Replaced my ignition switch with a 2 pole switch. Just use the 2 ...15 amp red and black wires.
The other 2 wires go to the ECU and earth it when ignition is turned off so it can't be hot wired by cutting and joining the red n black.
The 2 10 amp striped wires just need to be isolated and connected together (not with the red/black) to get ignition and motor started. (join red and black together only then join the 2 striped only together)
Check page 11 on my rebuild thread..
http://www.trx850.com/phpBB_forum/viewt ... &start=150
That should crank the motor and give you spark.
Why you have lost power to the dash may be an earth issue. There is one near the coils and your main earth from the battery.

One wire goes to the Starter cutoff relay, as well as the Ecu, I have tested the continuity of this item, according to the service manual it should have some resistance (if I am reading it correctly) but I get nothing on the dmm.
The battery is fine at 12.8v. Everything was fine until I connected the red wire and the blue/white wire.

So what happens when you just join the 2 heavier red and black cables from the ignition barrel together????
That should give you power...
Plug in head light or try indicators....
You won't have spark at the plugs though until you join the 2 smaller striped wires together.
Don't join all four together you'll get nowhere as this will earth the whole thing via the ecu cut out/ clutch lever/ side stand circuit.
But first, check your battery voltage once again

Sorry, it was the L/Y (blue and yellow).
There is no power to the red wire at present, just checked with dmm.

You may have earthed the main power straight from the battery.
If I remember correctly when sorting out my ignition, I put a multi meter on the battery and checked voltage and found a massive drop in voltage at the battery when I touched the striped cables to the red power cable for a second or 2 because as I mentioned, 1 striped cable runs to the ECU and the other striped cable to the earth circuit for the side stand /clutch lever.
Now remember this earth circuit is only purely for the ECU hence why it only breaks the earth to the ECU and power to the coils.
If you join power to either of the striped cables you'll either run + straight to earth or drive + power into the - earth connection for the ECU.
Main power from the battery runs from the battery to the starter relay so start checking power at battery, then move to your starter relay and follow the chain.

check battery fluid levels to make sure you haven't boiled the battery

3 main fuses later, the problem is resolved, both the original and the spare were faulty, pinched the spare from the car and it worked.
I have tested connecting the red and brown/blue (on mine, not black) and connecting the other two to each other, this also worked.
Will now connect up my remote switch to a new plug half so that I can plug into the loom.
Thanks for all of your assistance.

Have installed the remote control switch in place of the std ignition switch, working well.
Bought on Ebay for $8.00.