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C1799CriticalBrakes / Electronic Parking Brake

C1799 on 2007-2015 Jaguar XK (XK, XKR, XKR-S) — EPB Hall Effect Sensor Failure (Hall Sensor Plausibility)

1 vehicles · 1 makes · $500-$1,300 repair

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Most Reported On

2007-2015Jaguar XKXK +2

C1799 is an OBD-II diagnostic trouble code meaning “EPB Hall Effect Sensor Failure (Hall Sensor Plausibility).” The Electronic Parking Brake actuator uses Hall-effect sensors to count motor revolutions so the module can measure cable travel and applied clamp load. C1799 sets when those Hall sensor signals are missing, erratic, or implausible relative to the commanded motor operation, so the module cannot verify how far the actuator has travelled. Like C1785, Jaguar notes this fault is only detectable while the EPB motor is actually running. This code is most commonly reported on 2007-2015 Jaguar XK (XK, XKR, XKR-S), with repair costs ranging from $500 to $1,300.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (2)
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Common Causes

1Failed Hall-effect sensor inside the EPB actuator assembly
2Open, shorted or chafed Hall sensor signal / supply wiring to the actuator
3Corroded or moisture-contaminated actuator connector (rear underbody exposure)
4Worn or seized actuator gearbox producing implausible travel counts
5Failed EPB control module

Typical Repair Cost

$500 - $1,300

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

C1799 does not use the standard P/B/C/U prefix. It may be a manufacturer-specific code, so verify that a scanner supports your exact year, model and module before buying.

Vehicles Affected (1)

Jaguar C1799 page →
XKModerate

Electronic Parking Brake (EPB) Motor / Module Failure

2007-2015$500-$1,300

Related Codes (1)

C1785EPB Motor Output Open Circuit

FAQ

What does C1799 mean?

C1799 stands for "EPB Hall Effect Sensor Failure (Hall Sensor Plausibility)." The Electronic Parking Brake actuator uses Hall-effect sensors to count motor revolutions so the module can measure cable travel and applied clamp load. C1799 sets when those Hall sensor signals are missing, erratic, or implausible relative to the commanded motor operation, so the module cannot verify how far the actuator has travelled. Like C1785, Jaguar notes this fault is only detectable while the EPB motor is actually running.

What are the most common causes of C1799?

The most common causes of C1799 are: Failed Hall-effect sensor inside the EPB actuator assembly, Open, shorted or chafed Hall sensor signal / supply wiring to the actuator, Corroded or moisture-contaminated actuator connector (rear underbody exposure), Worn or seized actuator gearbox producing implausible travel counts, Failed EPB control module. The specific cause varies by vehicle.

How much does it cost to fix C1799?

Repair costs for C1799 range from $500 to $1,300, depending on the vehicle and root cause.

Which vehicles are affected by C1799?

Au7o has documented C1799 across 1 vehicle models from 1 manufacturers: Jaguar.

Sources (2)

  • ForumParking brake defective again? - Jaguar Enthusiasts Forum (X150)
  • ForumEPB stuck ON - can't move car! - Jaguar Forum
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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