Fix P2159: Mechanic’s solutions that WORKED

The P2159: Vehicle Speed Sensor B Range/Performance signifies a problem with the ‘Vehicle Speed Sensor B’, indicating an issue with its range or performance. This sensor plays a crucial role in informing the vehicle’s system about the wheel speed, which affects the speedometer and can impact the ABS system. A malfunction in this sensor can lead to incorrect speedometer readings and potentially affect the vehicle’s stability and braking systems.

P2159 quick overview

Meaning	P2159: Vehicle Speed Sensor B Range/Performance
Is it serious?	This code can be serious as it affects the vehicle’s speedometer readings and potentially the ABS system.
Possible causes	– Faulty or failing wheel speed sensor – Damaged or corroded wiring and connectors to the sensor – Issues with the ABS or stability control module – Incorrectly installed or damaged wheel bearings – Electrical issues in the vehicle’s speed sensing system
How to diagnose?	Inspect Wheel Speed Sensors: Check the condition and operation of the wheel speed sensors. Check Wiring and Connectors: Examine the sensor wiring and connectors for any signs of damage or corrosion. Use Oscilloscope: Utilize an oscilloscope to assess the wheel speed sensor signal waveform. Compare Sensor Outputs: Compare the readings from the problem sensor with other wheel speed sensors. Scan Tool Monitoring: Use a diagnostic scan tool to monitor real-time data from the wheel speed sensors. Evaluate Recent Repairs: Review any recent repairs related to the wheels or bearings that might affect sensor operation.

How to fix P2159 – learn from mechanics

I looked into P2159 service cases at iatn.com website where in the private forums the mechanics seek advice from other mechanics. I looked up a bunch of cases to help you decide how to fix your issue and see what would a real mechanic do to solve it.

Case #1: Saab

Vehicle Information: 2005 Saab 9-3 Linear 2.0L

Issue + Repair History:

• Multiple codes: P2128, P2138, P2159.
• Engine runs terribly; revs to 6000+ RPMs when put in Park and braking.
• Initially revved to 3000 RPMs but worsened over time.
• Accelerator pedal position sensor/switch replaced.
• Potential bad wiring harness identified.

Other OBD2 Codes + Test Results:

• P2138: Pedal Position Fault
• P2128: Pedal Position Fault
• P2159: Vehicle Speed Sensor Signal Out of Range
• P0455: Evap Valve Leak
• P0441: Canister Purge Valve Leak

Suggestions to Fix Issue:

• Monitor pedal position sensor operation.
• Check the 24-pin connector under the battery for acid damage.
• Investigate evap codes; potential issues with gas cap or rubber elbow for evap hose.
• Check vehicle speed sensor signal and throttle position.

Final Fix:

• Found a problem/break in the main harness, likely from a past accident.
• Customer opted not to proceed with further repairs. Vehicle returned to owner.

Case #2: Kia

Vehicle Information: 2008 Kia Optima LX 2.4L

Issue + Repair History:

• Code P2159 present.
• No ABS system; one speed sensor on right front spindle.
• Speedometer works but vehicle speed reads 0 in data pid.
• Original speed sensor resistance off; replaced with new sensor.
• Problem persisted after replacing sensor and used PCM.

Other OBD2 Codes + Test Results:

• P2159: Vehicle Speed Sensor B Range Performance

Suggestions to Fix Issue:

• Check magnetic strip or tone ring for the ABS sensor.
• Monitor output via scan tool.
• Check continuity from sensor connector to PCM.
• Verify integrity of reluctor ring on the axle and sensor gap.
• Check resistance between ECM terminals and matching WSS terminals.
• Inspect signal at ECM terminals 55 and 56.
• Check junction box for corrosion issues.
• Tighten half-shaft nut to the hub.
• Check for recent CV shaft changes and compare tone rings.

Final Fix:

• The first speed sensor from the dealer was faulty.
• Replaced with another new sensor from the dealer, which resolved the issue and the code did not return.

Case #3: Hyundai

Vehicle Information: 2013 Hyundai Genesis 3.8 3.8L

Issue + Repair History:

• No speedometer function, ABS, Brake, ETC, and CEL lights on.
• Difficulty in understanding the system’s operation.
• Front wheel speed sensors (WSS) tested for resistance and voltage; issues found.
• No reference voltage to front sensors with key on, engine running (KOER).
• Suspected front right wheel speed sensor (FRWSS) problem.
• ESC module not communicating initially, later resolved.
• Found ESC 10 amp fuse blown.

Suggestions to Fix Issue:

• Check for continuity in the wheel speed sensor.
• Scope the wheel speed sensor signal.
• Monitor the speed sensor through a scan tool connected to the brake module.
• Check for ESC module communication.
• Inspect wheel speed sensors for voltage changes.
• Look for wiring or connector issues, especially corrosion.
• Swap speed sensor with a known good one for testing.
• Use a small bulb in place of a fuse to detect a short circuit.

Final Fix:

• Replaced blown ESC 10 amp fuse with a 10 amp breaker.
• Monitored for reoccurrence of the issue while using a breaker for testing.
• No report from the customer regarding the return of the problem.
• Short suspected but not confirmed; will continue to monitor.

Case #4: Toyota

Vehicle Information: 2011 Toyota Camry LE 2.5L

Issue + Repair History:

• MIL Lamp on, with code P2159 indicated.
• Speedometer intermittently functioning.
• No recent accidents or major repairs reported.
• Checked wheel speed sensors; front sensors appeared operational.

Other OBD2 Codes + Test Results:

• P2159: Vehicle Speed Sensor B Range/Performance

Suggestions to Fix Issue:

• Inspect wiring and connectors of wheel speed sensors for damage or corrosion.
• Test wheel speed sensors for consistent output signal.
• Verify the operation of the ABS module, as it might be affecting the sensor readings.
• Check for any recalls or technical service bulletins related to this issue.

Final Fix:

• Found corroded connector at the right rear wheel speed sensor.
• Replaced connector and cleaned the area to remove corrosion.
• Cleared the code and test drove; speedometer function returned to normal and the code did not reappear.

Case #5: Ford

Vehicle Information: 2014 Ford Focus SE 2.0L

Issue + Repair History:

• Engine light on, code P2159 displayed.
• Speedometer showing inaccurate readings.
• Recently replaced left rear wheel bearing.
• Checked wheel speed sensor signals with a multimeter; found fluctuations in the left rear sensor.

Other OBD2 Codes + Test Results:

• P2159: Vehicle Speed Sensor B Range/Performance

Suggestions to Fix Issue:

• Re-examine the installation of the recently replaced wheel bearing.
• Scope the wheel speed sensors to compare signal waveforms.
• Check for proper alignment and installation of the wheel speed sensor.
• Ensure no damage to sensor wiring during wheel bearing replacement.

Final Fix:

• Discovered improper installation of the left rear wheel speed sensor after the wheel bearing replacement.
• Reinstalled the sensor correctly and ensured proper alignment.
• Cleared the fault code and conducted a road test; speedometer readings normalized and code did not recur.

Advice	Brief Description of Diagnostic Step
Check Wheel Speed Sensors	Inspect wheel speed sensors for continuity, resistance, and signal output.
Inspect Wiring and Connectors	Examine wiring and connectors related to the wheel speed sensors for damage or corrosion.
Verify Sensor Signal with a Scope	Use an oscilloscope to check the waveform of the wheel speed sensor signals.
Compare Sensor Readings	Compare readings from the suspected faulty sensor with other wheel speed sensors to identify inconsistencies.
Check for Corrosion or Damage	Look for any signs of corrosion or physical damage, particularly at the sensor connectors.
Monitor Speed Sensor via Scan Tool	Use a diagnostic scan tool to monitor real-time data from the wheel speed sensors.
Ensure Proper Installation of Sensors/Parts	Recheck any recently installed components (like wheel bearings) that may affect the wheel speed sensors.
Investigate ABS/ESC Module Communication	Confirm that the ABS or ESC modules are communicating properly and are not causing sensor issues.