The gauge and the tail/brake lights get 12vdc from the ECU voltage regulator. They are in no way related to the headlights or handwarmers or starter/battery.
First thing to check with any electrical issue is the ground wire bundles. Those are mounted to the front bumper tab on the PTO side of the front overstructure... If you took any hits to the front bumper... and that tab broke off...or cracked... you can have issues. If the bolt came loose or there is corrosion you can have issues.
dttrusko is on the right track... The Chassis relay, red/white circuit, is what powers those items...That relay is triggered by the ECU.
If your sled starts and runs, but does not power up these items... then you have a faulty relay, Faulty relay ground or faulty wires from that relay (most likely relay)
To test if the relay and wiring is OK...pull the relay, Start the sled and put a jumper wire between the Solid-RED and the RED-with-WHITE-stripe connections in the relay connector on the harness.
DO NOT put the jumper wire on in the connector before starting the sled. Start the sled...let it idle...THEN put the jumper in.
Polaris Maunal:
Chassis Relay: The chassis relay on DC-CFI
models supplies power to the MFD gauge,
accessory plug and DC power test plug.
The chassis relay is activated by the ECU at
approximately 950 RPM. Below 950 RPM, all
power supplied by the ECU regulator/rectifier
(RED circuit) is used to power the ECU
and fuel pump.
If you need the relay... you can get one from NAPA, I believe PN AR606, or a cross ref from another parts store. Delco C1725A is a cross for that as well.
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