P0348 Code: Camshaft Position Sensor A Circuit High Bank 2
P0348: Prove the High Signal on the Correct Bank
Identify Bank 2 Sensor A, preserve cranking evidence, and separate circuit high from cam timing performance.
DIAGNOSTIC FOCUS
- FAULT TYPE
- Bank 2 camshaft position sensor A circuit high
- FIRST CHECKS
- Bank/sensor identity, power and ground, signal integrity, connector oil and target condition
Circuit high is an electrical direction; it is separate from camshaft range/performance and crank-cam correlation codes.
P0348 means Camshaft Position Sensor “A” Circuit High (Bank 2). The controller detected voltage or signal state above the expected range in the Bank 2 Sensor A camshaft-position input.
Bank 2 is the bank that does not contain cylinder 1, while Sensor A usually follows OEM intake/exhaust naming that must be confirmed. Save the complete scan and freeze-frame record before clearing anything, then use the exact VIN service information to identify the monitored circuit and approved test points.
What Does the P0348 Code Mean?
P0348 is the diagnostic label for Camshaft Position Sensor “A” Circuit High (Bank 2). Audi diagnostic material distinguishes the Bank 2 Sensor A family: P0345 circuit, P0346 range/performance, P0347 circuit low and P0348 circuit high. It is a monitor result, not a parts order, and it does not by itself prove that the sensor, camshaft, timing chain, or controller has failed.
Hall-effect, magnetoresistive and other sensor designs use different power, ground, bias and waveform behavior. The useful distinction is between an electrical high signal, a missing or distorted cam target, and a mechanical timing or correlation problem. That distinction determines whether the next test belongs at a connector, a power or ground path, a control signal, a hydraulic or mechanical system, or an operating-condition check.
A short to supply, open ground, poor connector, sensor internal fault, wrong air gap, damaged target or controller input can affect the signal, but timing-chain conclusions need separate correlation evidence. A scan tool can preserve operating context and compare related data, but it cannot replace a current wiring diagram, connector view, service precautions, and any specified breakout leads or measurement method. Do not import pin numbers, thresholds, or component locations from another model year.
Capture confirmed, pending and history codes, freeze frame, first-failure order, system voltage, and the conditions present when P0348 set.
Locate cylinder 1, Bank 2, Sensor A, its connector, power/reference, ground, signal, controller terminal, target wheel and any variable-cam actuator sharing the area.
Compare the Bank 2 signal and supported cam data with Bank 1 only when designs match, then use an approved scope or circuit test to prove high-state behavior.
P0348 Symptoms, Severity, and Driving Safety
The engine controller records the high input and may substitute a value.
Some systems need a valid cam phase signal for quick synchronization.
Fallback timing and disabled variable-cam control can affect operation.
Heat, oil intrusion or harness movement can disturb the signal.
Crank/cam or variable-timing faults can define a separate mechanical branch.
A redundant strategy can keep the engine running despite one invalid input.
P0348 can range from a warning with fallback operation to a no-start or stall concern. Diagnose promptly, especially with correlation codes, abnormal mechanical noise, oil-pressure warnings or severe running problems.
P0348 Causes and the Evidence That Separates Them
The strongest P0348 diagnosis explains the code definition, the captured operating conditions, and any companion codes with one testable fault path. Confirm bank and sensor identity before testing because a correct measurement at Bank 1 or Sensor B proves nothing about this circuit.
Signal Shorted to Supply
Harness damage or a bridged terminal can hold the signal high.
How to prove it: Isolate the sensor and controller sides using the diagram and approved voltage tests.
Check firstOpen or High-Resistance Ground
A weak sensor ground can raise the observed signal or corrupt switching.
How to prove it: Measure voltage drop under load and check shared sensor-ground companions.
Check firstPower or Reference Fault
Incorrect supply from a shared reference or shorted neighbor can distort the sensor output.
How to prove it: Compare specified supply at the connector and trace affected shared circuits.
Verify directlySensor Internal Fault
Internal electronics can stick high or fail with heat or oil intrusion.
How to prove it: Confirm power and ground, then compare signal behavior with the OEM waveform or switching test.
Verify directlyConnector, Oil, or Harness Damage
Oil wicking, loose terminals and rub-through can create intermittent high input.
How to prove it: Inspect seals and terminal fit, clean only by approved method and reproduce movement safely.
Verify directlyTarget or Timing Condition as a Companion
A damaged reluctor or mechanical timing issue can distort phase information, though not always as pure circuit high.
How to prove it: Use waveform and correlation evidence before any internal-engine conclusion.
Final branchCause lists are starting points. A new sensor cannot repair a shorted harness, weak ground, wrong bank diagnosis or damaged target. Test the circuit in its failed state when possible, document the result, and replace a part only after the measured evidence points to it.
Using UR1000 to Organize P0348 Evidence
The iCARZONE UR1000 Bidirectional Scan Tool with ECU Coding supports full-system diagnostics, available DTCs, freeze frame, ECU information and live data. For P0348, use those records to compare Bank 2 cam position status or angle with crank synchronization, Bank 1 when comparable, VVT command/actual, engine speed and voltage, while keeping the first-failure order intact.
The official product page advertises bidirectional control and ECU coding. Coverage varies by VIN, ECU and software. Do not assume a menu item can command a variable-cam actuator or relearn routine; active tests and parameter names are vehicle-specific, and a supported command is not proof that the connected component can physically respond.
Use approved breakout leads; do not pierce sealed wiring or short a reference to ground. Scope tests around a running engine require secure leads and clear routing. Disconnecting a sensor may change bias and must be interpreted by the wiring design.
iCARZONE UR1000 Bidirectional Scan Tool with ECU Coding
Use UR1000 to preserve cranking/running status, cam and crank synchronization, VVT data, voltage, freeze frame and companion codes, then follow the VIN-specific electrical and mechanical tests before authorizing parts.
Price and availability checked September 3, 2026. Prices shown are USD. Recheck the current offer, stock and required vehicle/function coverage before purchase.
How to Diagnose P0348 in 6 Evidence-Based Steps
Use this order to avoid erasing the event or chasing a plausible part without proof. A bank-identification error is easy to make and expensive, so document component location before disconnecting anything. A failed test should lead to the next branch in the OEM procedure; a passed test should narrow the search rather than trigger replacement.
P0348 Quick Diagnostic Path
-
1
Save the Event
- Record all codes, freeze frame, voltage, engine speed, cam/crank status and VVT data.
- Note whether the engine was cranking, starting, idling or under load when the fault set.
-
2
Identify Bank 2 Sensor A
- Locate cylinder 1, the opposite bank, Sensor A and its target from VIN information.
- Do not rely only on left/right orientation or a generic engine diagram.
-
3
Inspect Connector and Harness
- With power off, inspect oil, water, terminal fit, heat, rub points and previous repairs.
- Check shared reference or ground codes that may explain multiple sensor faults.
-
4
Test Supply and Ground Under Load
- Measure specified power/reference and ground voltage drop with approved probes.
- A no-load continuity result does not prove terminal or ground integrity.
-
5
Evaluate the Signal
- Use the OEM switching, frequency or waveform test and compare a known-good bank only when equivalent.
- If electrical switching is sound, follow target and correlation tests before timing disassembly.
-
6
Repair and Verify Sync
- Repair the proven circuit, sensor mounting, target or mechanical fault and complete any required relearn.
- Confirm reliable start, stable cam/crank status and monitor completion without return.
How to Fix P0348 and Verify the Repair
Repair Signal, Ground, or Supply
Restore the exact conductor, terminal, splice or reference path that fails testing.
Correct Connector or Sensor Mounting
Repair seals, terminal fit, oil intrusion source, air gap or mounting damage as specified.
Replace the Proven Sensor
Use the correct Bank 2 Sensor A part only after circuit and target checks support failure.
Repair Target or Timing Fault
Pursue reluctor, cam phaser or mechanical timing work only with waveform or correlation evidence.
Bank Identification and Scan
VIN-specific quoteAccurate mapping and cranking evidence can prevent wrong-side parts replacement.
Harness or Connector Repair
VIN-specific quoteAccess and oil or heat damage determine labor.
Sensor Replacement
VIN-specific quotePart cost may be modest, but access and relearn vary.
Timing or Target Repair
VIN-specific quoteInternal work is substantially larger and needs evidence-based estimating.
A completed repair should correct the proven fault and preserve the original evidence in the work record. Confirm normal Bank 2 signal switching, stable cam/crank synchronization, reliable start, appropriate VVT response and no return of circuit or correlation codes.
Clear codes only after the repair and baseline checks are complete. Run the specified monitor or road-test conditions, rescan every relevant module, and compare the post-repair data with the saved event. A code that does not return during a short idle period is not automatically a verified fix.
P0348 OEM Differences and DIY Limits
Bank orientation, Sensor A naming, sensor technology, signal bias and target design vary by engine. That is why the displayed OEM description, wiring diagram, component locator, terminal identification, test conditions, and service bulletin applicability must match the full VIN.
Which bank lacks cylinder 1, and is Sensor A intake, exhaust or OEM-defined?
What supply, bias and waveform does this sensor technology use?
What target inspection, relearn or mechanical timing procedure applies?
Some sensors share references and grounds; some require relearn while others self-learn after a specified cycle. Generic guidance can organize evidence, but it must stop before unverified terminal probing, module programming, high-energy work, or disassembly that requires special tools and cleanliness controls.
- Record all modules, freeze frame and first-failure order before clearing.
- Identify the bank and inspect an accessible connector with the engine off.
- Inspect accessible connectors and harness routing with power off.
- Use the correct wiring diagram and approved probes for any measurement.
- Do not probe near rotating belts, fans or timing components without qualified controls.
- Do not pierce sealed wiring or spread terminals to obtain a reading.
- Do not run unsupported active tests or programming routines.
- Escalate when the procedure requires special tooling, disassembly, or controlled hazards.
Frequently Asked Questions About P0348
What does circuit high mean in P0348?
Does P0348 prove the sensor is bad?
Which side is Bank 2?
Is Sensor A always the intake cam?
Can I drive with P0348?
Can UR1000 show cam timing?
Does a correlation code mean the same thing?
How is repair verified?
Sources and Technical Review Notes
- Audi Quick Reference Specification Book — Lists the Bank 2 Sensor A family and distinguishes P0348 circuit high from circuit, performance and low directions.
- SAE J2012 Digital Annex — Provides current code-definition and failure-type provenance; engine-specific implementation remains with the manufacturer.
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