You saw C0708 and it points to a chassis steering‑sensor signal plausibility issue in SAE-style terms, meaning the vehicle’s steering-related sensor or its circuit is reporting a value outside expected range or not matching other inputs. SAE J2012 defines the DTC structure but many chassis codes do not map to one universal component; exact interpretation varies by make, model, and year. Diagnose test-driven: verify power, ground, wiring, connectors, and Controller Area Network (CAN) communications before assuming a failed module or sensor. Use basic electrical checks and signal plausibility tests to confirm the fault.
What Does C0708 Mean?
Under SAE J2012 formatting, C0708 is a chassis-classified fault that indicates a steering-related sensor signal is implausible or out of expected range relative to other vehicle inputs. This guide follows SAE J2012 formatting and references the SAE J2012-DA digital annex where standardized DTC descriptions are published.
The code is shown here without a hyphen suffix (no Failure Type Byte present). If an FTB were present (for example, a “-1A” or “-63” suffix) it would identify a subtype or more specific failure mode; the base C0708 meaning remains a steering‑sensor signal plausibility condition. Interpretation and the exact affected component can vary by make, model, and year, so confirm with direct electrical and network testing rather than assuming a failed part.
Quick Reference
- System: Chassis — steering sensor signal plausibility (SAE-style)
- Code shown without FTB; an FTB would indicate a subtype
- Primary checks: power, ground, wiring/connectors, signal plausibility
- Network checks: Controller Area Network (CAN) message presence and integrity
- Tools: multimeter, oscilloscope, scan tool with live data and Mode $06
- Diagnosis approach: test-driven; do not replace parts without verification
Real-World Example / Field Notes
In the shop you’ll often see C0708 come in with the vehicle showing Electronic Stability Control (ESC) or Anti-lock Braking System (ABS) warnings, or with steering-related limp behavior. Common field patterns include intermittent faults that clear after driving and reappear in wet weather, suggesting wiring or connector corrosion rather than an immediate sensor failure.
Another common pattern is a persistent implausible angle reading on the scan tool that doesn’t change when the steering wheel is turned — this points to a missing or stuck signal feed, or a network message fault. Always capture freeze-frame and live data before taking physical action so you can reproduce the fault conditions during repair verification.
Technicians commonly associated C0708 with the steering sensor circuit or the messages used by the vehicle stability systems. Treat it as a plausibility condition rather than a guaranteed failed part: wiring, connectors, power/ground, sensor plausibility, or CAN message integrity are frequent culprits.
What Does C0708 Mean?
C0708 is a chassis-related Diagnostic Trouble Code (DTC) defined in SAE J2012-style wording as a steering sensor signal plausibility fault. SAE J2012 defines DTC structure and some standardized descriptions, and the SAE J2012-DA digital annex publishes standardized DTC descriptions used by many manufacturers. This guide follows that formatting and uses the standardized phrasing where applicable.
The code shown here is without a hyphen FTB (Failure Type Byte); when present an FTB would identify a subtype or specific failure-mode within the base code (for example intermittent vs. stuck/high/low). Some manufacturers map C0708 specifically to the steering-angle sensor, while others use it for broader steering-input plausibility checks or fused sensor inputs. Always verify with electrical and network testing before replacing components.
Quick Reference
- System: Chassis — steering sensor signal plausibility
- Code displayed without FTB; an FTB would indicate a subtype
- Primary checks: power, ground, wiring/connectors, sensor plausibility
- Network checks: CAN message presence and integrity
- Tools: multimeter, oscilloscope, scan tool with live data and Mode $06
- Diagnosis approach: test-driven; verify signals before replacement
Real-World Example / Field Notes
In one shop job a vehicle arrived with ESC and ABS warnings illuminated and C0708 stored. A scan tool showed a steering-angle value that was flatlined at a fixed number regardless of wheel position. The technician checked 12 V and ground at the steering angle sensor harness and found intermittent ground continuity when the column was moved. After repairing a chafed ground splice and confirming stable ground and proper CAN traffic, the fault cleared.
Another field pattern is intermittent C0708 that appears in wet weather or after washing; this often points to corroded connectors or pin push‑out rather than an internal sensor failure. Conversely, persistent implausible values with clean wiring and solid CAN traffic can indicate a receiving ECU input-stage problem, requiring module-level diagnostics only after external checks are exhausted.
Symptoms of C0708
- Warning lamps ESC or ABS dash lamp illuminated
- Steering-readout mismatch steering wheel angle vs. instrument/snapshot values disagree
- Stability control intervention unexpected or reduced ESC/TCS intervention
- Intermittent behavior code appears/disappears with movement or weather changes
- Flatlined data steering angle value frozen or stuck on scan tool
- Communication errors related CAN messages missing or intermittent
Common Causes of C0708
Most Common Causes
Wiring and connector faults are frequent causes: corroded or loose harness connectors at the steering angle sensor, chafed wires in the column, or poor ground connections. Power supply problems—intermittent 12 V or weak feed—can make a sensor report implausible data. CAN message loss or errors due to bus wiring faults, node wakeup problems, or intermittent module-to-module communication are also common.
Less Common Causes
Less commonly, the sensor itself may be producing implausible raw outputs, or the receiving control unit may be rejecting an otherwise plausible signal due to internal input-stage faults, calibration mismatch, or software errors. Module input-stage issues or firmware problems should be considered only after all external wiring, power, ground, and signal integrity tests pass.
Diagnosis: Step-by-Step Guide
Tools: good scanner with live data and freeze-frame, digital multimeter, oscilloscope, backprobe pins or breakout harness, wiring diagram, continuity tester, terminal cleaner, and basic hand tools.
- Read freeze-frame and live data with a scan tool. Record steering angle, rate of change, and related ABS/ESC parameters. Note when the code set and any environmental conditions.
- Check for an FTB or supplemental fault data in the scan tool; record any stored network errors or U‑codes that may indicate bus problems.
- Visually inspect wiring, connectors, and harness routing to the steering angle sensor and ABS/ESC module. Look for chafing, water intrusion, or pin corrosion.
- With ignition on, measure sensor 12 V power and ground at the sensor connector using a multimeter. Wiggle the harness while observing voltage for intermittent drops.
- Backprobe the sensor signal pin and, where possible, view the raw signal with an oscilloscope while applying steering inputs. Observe waveform shape, amplitude, and change with wheel/steering movement.
- If the signal is missing, noisy, or flat-lined, isolate wiring and connector faults by measuring continuity and resistance between the sensor and the ECU with ignition off and performing wiggle tests to reproduce the issue.
- Verify reference voltages and ground quality at both the sensor and the receiving module. Use voltage-drop testing across connectors under load to identify high-resistance joints.
- Scan the vehicle for network health. View CAN message presence and error counters, and verify bus voltage levels and termination where needed with the scope.
- Compare sensor raw waveforms to expected patterns or to opposite-side sensors where applicable. If external inputs are confirmed good but values are rejected, follow OEM module-level diagnostics.
- Document findings, clear codes, and perform a controlled road test or activation routine while logging live data. Reproduce freeze-frame conditions to confirm repair and ensure the code does not return.
Use test-driven checks focused on wiring, power/ground, sensor plausibility, and network message integrity. SAE J2012 defines DTC structure and standardized descriptions; many chassis codes like C0708 do not map to a single universal component across makes and models. Confirm the fault with basic electrical and CAN/LIN checks before assuming a specific part.
Symptoms of C0708
- ABS Warning lamp illuminated on the dash, often steady or accompanied by traction control indicators.
- Pulsating Brake pedal felt during normal braking even at low speeds or in light city driving.
- Loss of Traction control or electronic stability interventions that engage unexpectedly.
- Inconsistent Speed readout from vehicle speed display or erratic speedometer behavior in some vehicles.
- Reduced Braking performance messages or limp-mode warnings in systems that limit ABS function.
- Intermittent Faults where the warning lamp clears after restart but returns under specific conditions like cornering or wet roads.
Common Causes of C0708
Most Common Causes
- Wiring harness damage or connector corrosion on wheel-speed/speed-sensor circuits, commonly exposed to road splash and movement.
- Intermittent sensor signal due to sensor air gap, contamination, or tone-ring damage causing implausible readings.
- Power or ground faults to the ABS module or sensor supply circuits causing unreliable input data.
- Loss or corruption of CAN messages between ABS and other modules producing a plausibility fault.
Less Common Causes
- Internal processing or input-stage issue in the ABS or related chassis control module after external inputs test good.
- Chassis harness chafing causing intermittent short to battery or ground under load conditions.
- Aftermarket electrical installs or past battery disconnects that changed sensor reference or module calibration leading to a mismatch.
Diagnosis: Step-by-Step Guide
Tools: diagnostic scan tool with live-data and CAN diagnostics, digital multimeter, oscilloscope, chassis wiring diagrams, back-probe pins or breakout box, pin-pullers, contact cleaner, and basic hand tools.
- Connect a diagnostic scan tool and record freeze-frame and live data for wheel-speed sensors and ABS status. Verify C0708 presence and whether an FTB is logged.
- Monitor wheel-speed sensor signals with live data while spinning each wheel by hand or during a slow drive; check frequency and plausibility relative to vehicle speed.
- Use an oscilloscope to view raw sensor waveforms; look for clean AC sine or square-ish signals without dropouts or excessive noise.
- Backprobe sensor harness connectors and measure reference supply voltage and ground under operating conditions; confirm stability within expected ranges.
- Perform wiggle tests on harnesses and connectors while observing live data to detect intermittent opens or shorts caused by movement.
- Check CAN bus health: view message presence, bus load, and error counters. Verify termination and voltage levels where required.
- Inspect tone rings, sensor mounts, and surrounding hardware for damage, contamination, or misalignment that could alter signal amplitude or timing.
- If wiring, power, ground, and sensor waveforms test good, compare module-reported inputs to measured harness values and consult manufacturer-specific module tests before replacement.
- Clear codes and perform a road test under the original fault conditions to confirm repair or to capture repeatable failure data for further diagnostics.
Professional tip: always verify sensor plausibility and network message integrity before replacing an ABS or chassis module. A confirmed internal module issue should be diagnosed only after exhaustive wiring, power/ground, waveform, and CAN/LIN checks show correct external conditions.
SAE J2012 classifies C-codes as chassis system faults; C0708 is a chassis-level signal plausibility indication tied to wheel-speed, brake-speed, or steering-speed sensor signals and their associated circuitry. Many chassis codes do not map to a single universal component — verify per-vehicle wiring and module architecture and confirm the fault with electrical and network testing before assuming a failed part.
Possible Fixes & Repair Costs
Low-cost fixes (low): $40–$120 — cleaning a corroded connector, reseating a sensor plug, or repairing a terminal. Typical repairs (typical): $150–$450 — replacing a single wheel-speed or steering-angle sensor or repairing a damaged pigtail after waveform testing. High-cost repairs (high): $500–$1,200+ — complex harness repair, axle harness replacement, or module replacement/programming. Only justify module replacement after all external wiring, connectors, power, ground, and CAN/LIN checks pass and Mode $06 or live-data confirm correct inputs. Labor, part pricing, and need for programming affect final cost.
Can I Still Drive With C0708?
You can often drive short distances with C0708 present, but it depends on how the code affects braking and stability systems. If the fault disables or degrades ABS, ESC, or TCS, you may have reduced stability and longer stopping distances. Drive cautiously to a safe location or repair shop and avoid high-speed or low-traction conditions until the issue is resolved.
What Happens If You Ignore C0708?
Ignoring C0708 can allow an intermittent or degrading sensor or wiring issue to persist, possibly disabling ABS/ESC/TCS when needed and increasing crash risk. Persistent faults can cascade into additional warnings and may mask other faults, complicating later diagnostics and repairs.
Related Codes
- C0767 – Brake Control Signal Plausibility (Chassis)
- C0766 – Tire Pressure Monitor System – High Tire Pressure
- C0765 – Wheel Speed Sensor Signal Plausibility - Chassis
- C0764 – Tire Pressure Monitor System – Low Tire Pressure (Right Rear)
- C0763 – Steering Sensor Signal Plausibility
- C0762 – Brake Pressure Signal Plausibility
- C0761 – Brake Pressure Signal Plausibility
- C0759 – Steering Assist Communication Fault
- C0758 – Tire Pressure Monitor Sensor Circuit Range/Performance
- C0757 – Steering Angle Signal Circuit Fault
Key Takeaways
C0708 is a chassis-level plausibility fault related to steering or wheel/brake-speed sensor signals or their circuitry. Always test power, ground, signal waveform, and network messages before replacing parts. Start with connector inspection, then measure supply and ground, verify sensor output with a scope, and confirm CAN/LIN message integrity. Treat module replacement as a last resort after exhaustive external verification.
Vehicles Commonly Affected by C0708
Commonly seen on vehicles from Toyota, Ford, BMW, and on many modern SUVs and light trucks that use multiple wheel-speed and steering sensors with integrated ABS/ESC networks. These platforms often have long harness runs exposed to corrosion or road damage and tighter ABS/stability integration that can produce plausibility faults. Always check the vehicle-specific wiring diagram and OEM documentation.
FAQ
Can I clear C0708 with a scan tool and see whether it returns?
Yes — clearing the code is a valid first diagnostic step. After clearing, drive through the conditions that originally set the code while monitoring live data or Mode $06. If the fault returns, capture live-waveforms and freeze-frame data to guide targeted electrical testing rather than guessing at repairs.
Is a failed wheel speed sensor the most likely cause of C0708?
Not always. A wheel speed or steering-angle sensor is a common association, but wiring, connectors, corroded grounds, or CAN/LIN message loss are equally plausible. Use a multimeter and scope to check sensor AC/frequency output and supply voltages before replacing the sensor.
What diagnostic tests confirm a wiring or connector issue for C0708?
Start with visual inspection, then continuity and resistance measurements across the suspect harness with connectors disconnected. Backprobe to verify supply and ground with ignition on. Use an oscilloscope to watch the waveform while spinning the wheel or applying steering input and perform wiggle tests on the harness to reproduce the fault. If the waveform drops out or voltages vary when manipulating connectors, repair the wiring or connector.
Can a bad CAN bus cause C0708 even if sensors look OK?
Yes. If sensor data is not reaching the ABS or chassis module due to CAN/LIN interruptions, a plausibility fault may be set. Confirm by viewing network traffic with a diagnostic tool. If the sensor produces a clean waveform but corresponding network messages are missing or error-laden, focus on CAN termination, wiring, and module power/ground checks.
How long will a proper repair for C0708 typically take?
Repair time varies by root cause: a connector clean and reseat can be under an hour, while harness repair or sensor replacement is two to four hours. Module-level interventions after exhaustive external tests can take longer due to diagnostics and programming. Base the repair time and cost on documented diagnostic findings such as failed continuity, waveform, or voltage tests.