Brake Wire Location | Axon Fleet 3 & 12 Volt Troubleshooting

Brake Circuit Reference

Brake Wire Location & Verification

Find the correct brake wire for brake-triggered equipment (radar interfaces, camera event triggers, light bars, and brake lights). Always confirm the circuit with a meter — never trust wire color alone.

Safety first: The brake circuit feeds the stop lamps and can also feed ABS, stability control, and cruise-control modules. Use a fused tap or an approved connector, never cut or splice a brake wire that also serves a factory safety system, and verify with the current vehicle service information before connecting.

Locate the brake switch

☐ The primary brake wire access point is the brake pedal switch on the pedal assembly under the dash.
☐ Remove the under-dash knee bolster/trim panel for access; support the panel so the harness is not strained.
☐ Identify the switch connector: most vehicles have one circuit set for the stop lamps and a second set for the PCM/ABS signal.
☐ On police packages, a blunt-cut brake lead may already be provided in the upfitter harness — prefer this dedicated lead.

Identify the circuit type

☐ Hot at rest (+12V when pedal up): Common on older/simple stop-lamp circuits. The switch applies ground (or opens) when pressed — verify which transition your equipment expects.
☐ Ground at rest: The switch applies battery voltage when the pedal is pressed. Common on many late-model vehicles.
☐ CAN-reported: Many modern vehicles report brake status on the data bus only, with no dedicated 12V brake wire at the switch — do not assume a wire is present.
☐ Check the vehicle upfitter guide (Upfitter Diagrams tab) for the documented brake tap point and wire color for the exact model year.

Verify with a multimeter

☐ Back-probe the switch connector with a meter or test light; do not puncture the insulation.
☐ Pedal up: record the reading (12V, 0V, or a bus/complex signal).
☐ Pedal down (brakes applied): record the reading again — the state must change cleanly every press.
☐ Confirm the transition direction (hot-at-rest vs ground-at-rest) matches what your brake-triggered device expects before connecting anything.

Connect and test

☐ Tap with an approved fuse tap, sealed connector, or solder + heat-shrink — never a bare twist or tape alone.
☐ Fuse any added lead close to the tap point and keep the routing away from pedals, airbags, and moving columns.
☐ Test every pedal press: the triggered device must respond instantly and release cleanly, with no brake-lamp warnings or DTCs.
☐ Re-check ABS, cruise control, brake lamps, and start/stop behavior before releasing the vehicle.

Brake wire location — quick reference by vehicle

Chevrolet Tahoe (PPV / SSV)

Brake switch wire is brown/yellow, found in the police package wiring — either at the rear of the vehicle or at the center console. Verify hot-at-rest vs ground-at-rest with a meter before tapping.

Dodge Durango (Pursuit)

Brake switch wire is green/orange, at pin 4 of the 24-pin white plug on the ViSM module behind the rear passenger seat. Verify the state change with a meter before connecting.

Ford Police Interceptor (Utility / Sedan)

Brake switch wire is gray/brown, at pin 8 in the white connector in the center console. Verify the state change (pedal up vs pedal down) with a meter before connecting.

Ford F-250 Super Duty

Brake switch wire is light green, found in the driver's sill plate (kick-panel area at the door sill). Confirm hot-at-rest vs ground-at-rest with a meter before tapping.

Dodge Ram 1500/2500/3500

Brake switch wire is white/green, found in the driver's sill plate. Verify the state change (pedal up vs pedal down) with a meter before connecting.

Ford F-150

Brake switch wire is gray/orange at the black plug in the passenger kick panel. Confirm the circuit behavior with a meter — wire colors can change by model year.

Chevrolet Silverado 1500/2500

Brake switch wire is white/blue at the BCM green plug. Verify the signal at the connector with a meter before tapping — the BCM circuit may be CAN-related.

Source note: Wire colors and switch pinouts change by model year and option package. Always confirm in the vehicle-specific upfitter guide (see the Upfitter Diagrams tab) and with a meter before connecting.