I've written about this on a previous thread, however want to introduce a slight twist to the narrative.
Our Rocket III ECU CDI controller can be found under the side-cover on the right side of the bike.
Sitting right on top proudly can be seen two very large serial connectors with rubber boots on them
First point to make - don't assume that just because there is a nice rubber boot protecting those connectors - water never gets in there
I pulled both those connectors and could clearly see blue residue caused by corrosion from moisture. Sprayed both ends with electrical contact cleaner and scrubbed them with an old toothbrush to remove the corrosion.
Probably a good idea to check those once in a while
Now that CDI controller talks to the Instrument cluster (it's LAN or CAN) via a serial BUS (previous thread)
You ever see error code P1690 it means, your ECU can't talk to the CAN
Second point - if you trace back the wiring from the Instrument cluster or gauges into the harness and under the tank, (unfortunately Triumph does not terminate in a nice Bosch connector like the ignition switch does) - it splices straight into the loom
HINKLEY HINT
If for whatever reason - you are unfortunate enough to find that you've lost power to your gauges, getting error code P1690, then when you go into the diagnostics screen on a service laptop, switch to manual on that CDI controller - select 'body' you will be able to manually turn on and off each component or sensor, i.e. the fuel pump, gauges and so on.
If you have an interruption in that harness between the splice and the back of the gauges, it'll come back and tell you - 'gauges unplugged'. Yet you look up and there they are, plugged right in.
So, back to the wiring diagram and start hunting
Nowhere in that wiring diagram does it say anything about a purple wire.
Yet strip that harness and start peeling back from the gauges, there it is - a purple wire.
Under the tank and powered, it's what powers the Instrument cluster (C.A.N.)
In my case - a 2013 Rocket III Roadster, that purple wire showed evidence of heat wear.
Not heat damage, burnt or broken, just dried up and rather sorry looking for such an important role.
Herein therefore lies the cautionary note - if you find you've lost power to your gauges, getting a serial BUS error and have torn all your hair out trying to check relays, connectors, fuses, harness and ECM - peel back from those gauges and find the little purple wire.
It was my culprit
*Note: one final post-script - the ECU on a Rocket III is adaptive
That's worth remembering when you wonder why it seems to take a while for the ECU to settle down.
Our Rocket III ECU CDI controller can be found under the side-cover on the right side of the bike.
Sitting right on top proudly can be seen two very large serial connectors with rubber boots on them
First point to make - don't assume that just because there is a nice rubber boot protecting those connectors - water never gets in there
I pulled both those connectors and could clearly see blue residue caused by corrosion from moisture. Sprayed both ends with electrical contact cleaner and scrubbed them with an old toothbrush to remove the corrosion.Probably a good idea to check those once in a while
Now that CDI controller talks to the Instrument cluster (it's LAN or CAN) via a serial BUS (previous thread)
You ever see error code P1690 it means, your ECU can't talk to the CAN
Second point - if you trace back the wiring from the Instrument cluster or gauges into the harness and under the tank, (unfortunately Triumph does not terminate in a nice Bosch connector like the ignition switch does) - it splices straight into the loom
HINKLEY HINT If for whatever reason - you are unfortunate enough to find that you've lost power to your gauges, getting error code P1690, then when you go into the diagnostics screen on a service laptop, switch to manual on that CDI controller - select 'body' you will be able to manually turn on and off each component or sensor, i.e. the fuel pump, gauges and so on.
If you have an interruption in that harness between the splice and the back of the gauges, it'll come back and tell you - 'gauges unplugged'. Yet you look up and there they are, plugged right in.
So, back to the wiring diagram and start hunting
Nowhere in that wiring diagram does it say anything about a purple wire.
Yet strip that harness and start peeling back from the gauges, there it is - a purple wire.
Under the tank and powered, it's what powers the Instrument cluster (C.A.N.)
In my case - a 2013 Rocket III Roadster, that purple wire showed evidence of heat wear.
Not heat damage, burnt or broken, just dried up and rather sorry looking for such an important role.
Herein therefore lies the cautionary note - if you find you've lost power to your gauges, getting a serial BUS error and have torn all your hair out trying to check relays, connectors, fuses, harness and ECM - peel back from those gauges and find the little purple wire.
It was my culprit
*Note: one final post-script - the ECU on a Rocket III is adaptive
That's worth remembering when you wonder why it seems to take a while for the ECU to settle down.
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