P1429 on 2014-2018 Chevrolet Silverado — Brake System Vacuum Pump Activation: Open Circuit
1 vehicles · 1 makes
How to diagnose and fix P1429: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Chevrolet Silverado · 2014–2018
GM recalled about 3.46 million vehicles (NHTSA 19V645 and expanded 20V603), including 2014-2018 Silverado 1500, for an engine-driven brake vacuum pump that loses output over time. Debris and oil sludge build up on the pump's internal filter screen, reducing the vacuum that powers the brake booster. The result is a hard/firm brake pedal requiring much more effort and increased stopping distance, with a 'Service Brake Assist' message. GM attributed 113 accidents and 13 injuries to the condition. Notably, the recall remedy is a software recalibration of the electronic brake control module to add hydraulic boost when vacuum is low — it is NOT a replacement of the failing pump itself, so the underlying P1429 vacuum-pump complaint persists for many owners. High search and complaint volume.
Common Symptoms
- Hard / firm brake pedal needing much more effort
- Increased stopping distance
- 'Service Brake Assist' message on the DIC
- Pedal effort worse on cold starts / first stops
- Ticking or clattering from the vacuum pump area
How to Fix
Check VIN against recalls 19V645 / 20V603 and have the dealer apply the free EBCM software recalibration that activates secondary hydraulic boost when vacuum drops. Because the recall does not replace the pump, owners experiencing a persistently hard pedal or P1429 typically need the mechanical vacuum pump replaced (and the engine oil kept clean, since oil sludge clogs the pump screen). Replace the pump with an updated unit if it is the cause.
Sources for this issue (1)
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P1429 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P1429 mean?
P1429 stands for "Brake System Vacuum Pump Activation: Open Circuit." Manufacturer-specific code used by Volkswagen and Audi; Ross-Tech lists it as VAG code 17837 with the fault text "Circuit for Brake Vacuum Pump: Open Circuit." The control module commanded the electric brake vacuum pump on and detected an open in the pump's activation circuit, so the pump did not respond as expected. Manufacturer documentation lists the check engine light as the confirmed symptom; on vehicles that depend on this pump for power-brake assist, a genuinely dead pump can also make the pedal noticeably harder and lengthen stopping distances. Other manufacturers assign different meanings to P1429, so confirm the definition against the vehicle's make before diagnosing.
What are the most common causes of P1429?
The most common causes of P1429 are: Failed electric brake vacuum pump (most common), Blown vacuum pump fuse or failed relay, Open, chafed, or corroded wiring between the module and the pump, Corroded or backed-out connector pins at the pump, Faulty brake booster control module (J542). The specific cause varies by vehicle.
How much does it cost to fix P1429?
Repair costs vary widely depending on the root cause and vehicle.
Which vehicles are affected by P1429?
Au7o has documented P1429 across 1 vehicle models from 1 manufacturers: Chevrolet.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.