If you're experiencing brake problems, it's highly unlikely the proportioning valve itself needs "resetting". Instead, the issue likely lies elsewhere. Possible causes for brake problems include:
* Low brake fluid: Check your brake fluid level in the master cylinder reservoir. Low fluid indicates a leak somewhere in the system.
* Worn brake pads or shoes: Worn brake pads/shoes require replacement.
* Faulty brake calipers or wheel cylinders: These can leak or seize, causing uneven braking.
* Air in the brake lines: Air in the brake lines will cause a spongy brake pedal and reduced braking effectiveness. This requires bleeding the brakes.
* Faulty master cylinder: A failing master cylinder can cause a variety of brake problems.
* Faulty ABS module (if equipped): The ABS system on your truck might have a problem. This usually requires diagnostics by a mechanic.
* A problem with the proportioning valve itself (rare): While you can't reset it, the valve itself could be internally faulty. This would require replacement by a mechanic.
Before attempting any brake repairs yourself: Brake systems are complex and safety-critical. Improperly repaired brakes can lead to serious accidents. If you're experiencing brake problems, it's strongly recommended that you take your truck to a qualified mechanic for diagnosis and repair. They have the tools and expertise to diagnose the problem accurately and safely repair it.
If you've recently had brake work done, a mechanic *might* have to bleed the brakes to remove any air introduced into the system during the repair, but this is not a "reset" of the proportioning valve itself.
