The Auras of Survivors, who are healing or being healed, are revealed to you when they are within a range of 20/24/28 meters.

After a Survivor loses a health state, Gearhead activates.

While Gearhead is active, the next time a Survivor completes a Great Skill Check while repairing, the perk deactivates and their aura is revealed to you for 10 seconds.

Each injured, dying, or hooked Survivor afflicts Survivors with a stack-able 1/1.5/2 percent Action Speed penalty to Repairing, Sabotaging, and Cleansing, up to a maximum of 4/6/8 percent.
Increases the Action Speed penalty by a further 12 percent, if there are 4 Survivors, who are either injured, dying, or hooked at the same time.

Whenever a Generator is repaired to 70 percent, you benefit from the following effects:
Triggers a Loud Noise Notification for that Generator, revealing its location.
Grants the Undetectable Status Effect for the next 12/14/16 seconds.
Tinkerer can only trigger once per Generator per Trial.