P0342 on a 2017 Ford Mustang
Cam Position Sensor Low Input (Bank 1)
P0342 on a 2017 Ford Mustang indicates cam position sensor low input (bank 1). It usually stays drivable short-term but should be diagnosed promptly. The most common cause is camshaft position sensor signal wire shorted to ground (typically $80–$350). Confirm the root cause before replacing parts.
What does P0342 mean on a 2017 Ford Mustang?
P0342 is set when the ECM sees the Bank 1 "A" camshaft position sensor circuit sitting below its calibrated minimum voltage. On most engines "A" is the intake camshaft, or the single cam sensor on engines that only have one. The usual explanation is a signal wire shorted to ground, an open circuit that lets the ECM's internal pull-down hold the line low, or a sensor that has failed to a low output. P0342 is a voltage-level fault — distinct from P0340 (no usable signal) and P0341 (signal present but out of spec).
The symptoms, causes, and diagnostic steps below describe P0342 itself, so they read the same on nearby Ford Mustang model years. Powertrain and trim details vary year to year — confirm the specifics against your own vehicle before buying parts.
Is it safe to drive a 2017 Ford Mustang with P0342?
In most cases a 2017 Ford Mustang stays drivable for short trips with P0342 active, but diagnose and repair it promptly. This is a high-severity code — ignoring it can lead to further damage or a failed emissions test.
What are the symptoms of P0342 on a 2017 Ford Mustang?
- Check Engine Light is illuminated
- Hard start with extended cranking
- Possible complete no-start condition
- Stalling, often when the engine is hot
- Rough running and noticeably reduced power
- Misfire-like stumbling if the ECM loses cylinder sync
- Reduced fuel economy
What causes P0342 on a 2017 Ford Mustang?
| Cause | Likelihood | Estimated repair (USD) |
|---|---|---|
| Camshaft position sensor signal wire shorted to ground | Most common | $80–$350 |
| Failed camshaft position sensor (output stuck low) | Most common | $100–$400 |
| Corroded or water-intruded sensor connector | Common | $50–$250 |
| Oil leaking into the cam sensor port and shorting the sensor internals Replace the o-ring along with the sensor or the new one fails the same way. | Common | $80–$350 |
| Open or high-resistance reference-voltage or ground circuit feeding the sensor | Occasional | $80–$350 |
| Damaged or slipped camshaft reluctor / tone wheel | Occasional | $300–$1,200 |
| Failed PCM input for the cam sensor circuit | Rare | $400–$1,500 |
Cost ranges are editorial estimates for parts and labor at an independent U.S. shop — not quotes. What you actually pay moves with your region, the shop's hourly rate, which engine you have, and how much diagnostic time the job takes. Dealer service departments typically sit above these ranges.
How to diagnose this on a 2017 Ford Mustang
-
Inspect the connector and harness at the cam sensor
The cam sensor usually threads into the cylinder head or the timing cover near the front of the engine. Unplug it and look for corrosion, spread or pushed-back pins, oil inside the connector body, and chafe marks where the harness passes a bracket. Fix what you find before testing further — a marginal connector produces exactly this code.
Tools: Connector unlock tool, Flashlight, Electrical contact cleaner
-
Back-probe the signal wire with the key on
With the sensor still connected and the key on, engine off, measure the signal wire against a good ground. A Hall-effect cam sensor normally rests high (near reference voltage) and pulls low as the reluctor passes. A signal line sitting at or near zero volts with the key on is the condition that sets P0342.
Tools: Multimeter, Back-probe pins, Wiring diagram
-
Run the disconnect test to split sensor from wiring
Unplug the sensor and measure the signal wire at the harness side, key on. If the voltage now rises to the ECM's reference level, the wiring is fine and the sensor was pulling it down — replace the sensor. If it stays pinned low with the sensor unplugged, the short to ground is in the harness, and a new sensor will change nothing.
Tools: Multimeter, Wiring diagram
-
Verify sensor power and ground
With the connector unplugged and the key on, confirm the supply voltage the wiring diagram calls for on the power pin, and a clean low-resistance path from the ground pin to chassis ground. A corroded ground makes a good sensor read low and sets P0342 with no fault in the sensor at all.
Tools: Multimeter, Wiring diagram
-
Scope the sensor while cranking
If the static tests all pass, capture the waveform during a crank. A healthy Hall sensor produces clean square pulses at consistent spacing. Pulses that are present but clipped low, or a trace that never leaves the baseline, confirm the sensor or its supply. Compare against the known-good waveform in the service manual.
Tools: Oscilloscope, Back-probe pins
Known Technical Service Bulletins for the 2015-2019 Ford Mustang
Manufacturers publish Technical Service Bulletins (TSBs) when a known issue affects a specific vehicle. These bulletins come from the NHTSA database for your Ford Mustang.
- UNKNOWN OR OTHER Feb 23, 2026
Ford and Lincoln vehicles equipped with wired keyless entry keypad systems and accessory wireless keyless entry keypad systems may or may not come with a wallet card containing the master code. Unlike the integrated wired keypad, the accessory wireless keypad master code cannot be retrieved from the vehicle using a diagnostic scan tool or from the label printed on the body control module (BCM). The Factory Keyless Entry Code application within the diagnostic scan tool will not provide an applicable master code for the accessory wireless keypad. If the wallet card for an accessory keypad is not available, the "Wireless RF Keypad Diagnosis Guide" can be referenced and provides direction on how to retrieve the master code. This guide is located under the Workshop Manual tab > Accessories > Installation > Wireless RF Keypad Diagnosis Guide > PPT C > Step C2.<br /><br /> Note: The only available keypad for some vehicles from the assembly plant is the accessory wireless keyless entry keypad. The integrated wired keypad cannot be installed on vehicles not equipped from the factory with a wired keyless entry k
NHTSA #11029052 - ELECTRICAL SYSTEM Feb 23, 2026
Ford and Lincoln vehicles equipped with wired keyless entry keypad systems and accessory wireless keyless entry keypad systems may or may not come with a wallet card containing the master code. Unlike the integrated wired keypad, the accessory wireless keypad master code cannot be retrieved from the vehicle using a diagnostic scan tool or from the label printed on the body control module (BCM). The Factory Keyless Entry Code application within the diagnostic scan tool will not provide an applicable master code for the accessory wireless keypad. If the wallet card for an accessory keypad is not available, the "Wireless RF Keypad Diagnosis Guide" can be referenced and provides direction on how to retrieve the master code. This guide is located under the Workshop Manual tab > Accessories > Installation > Wireless RF Keypad Diagnosis Guide > PPT C > Step C2.<br /><br /> Note: The only available keypad for some vehicles from the assembly plant is the accessory wireless keyless entry keypad. The integrated wired keypad cannot be installed on vehicles not equipped from the factory with a wired keyless entry k
NHTSA #11029052 - STRUCTURE Feb 23, 2026
Ford and Lincoln vehicles equipped with wired keyless entry keypad systems and accessory wireless keyless entry keypad systems may or may not come with a wallet card containing the master code. Unlike the integrated wired keypad, the accessory wireless keypad master code cannot be retrieved from the vehicle using a diagnostic scan tool or from the label printed on the body control module (BCM). The Factory Keyless Entry Code application within the diagnostic scan tool will not provide an applicable master code for the accessory wireless keypad. If the wallet card for an accessory keypad is not available, the "Wireless RF Keypad Diagnosis Guide" can be referenced and provides direction on how to retrieve the master code. This guide is located under the Workshop Manual tab > Accessories > Installation > Wireless RF Keypad Diagnosis Guide > PPT C > Step C2.<br /><br /> Note: The only available keypad for some vehicles from the assembly plant is the accessory wireless keyless entry keypad. The integrated wired keypad cannot be installed on vehicles not equipped from the factory with a wired keyless entry k
NHTSA #11029052 - VISIBILITY/WIPER Jan 5, 2026
Certain 2015-2019 Model Year Multiple Vehicle Lines Rear View Camera Inspection For One-Time Replacemen
NHTSA #11027801 - VISIBILITY/WIPER Dec 22, 2025
Certain 2015-2019 Model Year Multiple Vehicle Lines Rear View Camera Inspection For One-Time Replacement
NHTSA #11026915 - UNKNOWN OR OTHER Dec 22, 2025
Certain 2015-2019 Model Year Multiple Vehicle Lines Rear View Camera Inspection For One-Time Replacement
NHTSA #11026915
+14 more TSBs available in MECH AI's TSB explorer for this vehicle.
NHTSA complaints & recalls for the 2017 Ford Mustang
Owner-reported safety complaints and official recalls filed with the U.S. National Highway Traffic Safety Administration for the 2017 Ford Mustang. Use these to gauge how common a problem is on your specific vehicle before you start chasing Ford Mustang diagnostics.
- ENGINE 26
- BACK OVER PREVENTION 62
- UNKNOWN OR OTHER 36
- STRUCTURE 36
- ELECTRICAL SYSTEM 31
6 active recalls
- ENGINE AND ENGINE COOLING:COOLING SYSTEM:HOSES/LINES/PIPING/FITTINGS Oct 2016
Ford Motor Company (Ford) is recalling certain model year 2015-2017 Mustang vehicles manufactured February 24, 2015, to August 30, 2016. A hose may separate from the engine oil cooler tube assembly causing an oil leak.…
NHTSA campaign 16V779000 - AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE Aug 2017
Ford Motor Company (Ford) is recalling certain 2017 F-150 and Mustang vehicles. The air bag inflator within the passenger frontal air bag module may rupture in the event of a crash.…
NHTSA campaign 17V529000 - LATCHES/LOCKS/LINKAGES:DOORS:LATCH Mar 2017
Ford Motor Company (Ford) is recalling certain 2017 Ford Mustang vehicles. The return spring for the driver side interior door handle may come loose, allowing the driver's door to unlatch in a side impact crash. As such, these vehicles fail to comply with the requirements of Fe…
NHTSA campaign 17V168000 - BACK OVER PREVENTION: SENSING SYSTEM: CAMERA Feb 2022
Ford Motor Company (Ford) is recalling certain 2015-2017 Mustang vehicles. The rearview camera wiring may be loose or damaged, which can result in a blank or distorted image.…
NHTSA campaign 22V082000
How do I fix P0342 on a 2017 Ford Mustang?
- Replace the camshaft position sensor with an OEM part
- Repair the shorted-to-ground signal wire
- Repair or replace the corroded sensor connector
- Replace the cam sensor o-ring to stop oil intrusion
- Replace a damaged or slipped cam reluctor wheel
Engines in the 2017 Ford Mustang
The 2017 Ford Mustang was offered with the 2.3L 4-cylinder, 3.7L 6-cylinder and 5.0L 8-cylinder engines. Which one you have changes where P0342 is most likely to originate, so confirm your engine before ordering parts.
Engine data: EPA fueleconomy.gov.
P0340, P0341, P0342, P0343 — which one you have matters
All four are the same sensor. What differs is what the ECM measured, and that changes where you point the multimeter:
| Code | What the ECM saw |
|---|---|
| P0340 | No usable signal at all |
| P0341 | Signal present, but the pattern or timing is wrong |
| P0342 | Circuit voltage below the calibrated minimum |
| P0343 | Circuit voltage above the calibrated maximum |
P0342 and P0343 are the pair that most reliably points at wiring rather than at the sensor, because a specific voltage rail failure is usually caused by a specific wire touching something it shouldn’t.
The one test that saves the most money
Unplug the sensor and measure the harness-side signal wire with the key on. That single measurement splits the diagnosis cleanly:
- Voltage comes up to reference → the harness is good, the sensor was dragging the line down. Replace the sensor.
- Voltage stays low → the sensor was never the problem. The short to ground is in the harness, and you have wire to chase.
A cam sensor is a cheap part and a quick job on most engines, which is exactly why so many get replaced for nothing. Two minutes with a multimeter tells you whether yours is one of them.
Why a cam sensor fault can strand you
The ECM uses the cam signal to work out which cylinder is on its compression stroke rather than its exhaust stroke. Without a usable cam signal, many engines default to a fail-safe that cuts fuel injection entirely — the engine cranks and never fires. Others fall back to running on the crank signal alone in batch-fire mode, which runs, but roughly. Which behaviour you get depends on the manufacturer, so a P0342 that lets you drive today can still leave you stranded tomorrow.
The heat-soak pattern
If the code is intermittent and the trouble shows up after the engine is fully warm — stop for fuel after half an hour of driving, come back to a long crank or a no-start — that pattern points at a sensor whose internals break down as they heat up, or at oil that has worked its way into the sensor body. Both get worse over time. Fix it on your schedule rather than on the side of a road.
P0342 on a 2017 Ford Mustang: frequently asked questions
What does diagnostic trouble code P0342 mean on a 2017 Ford Mustang?
P0342 is set when the ECM sees the Bank 1 "A" camshaft position sensor circuit sitting below its calibrated minimum voltage. On most engines "A" is the intake camshaft, or the single cam sensor on engines that only have one. The usual explanation is a signal wire shorted to ground, an open circuit that lets the ECM's internal pull-down hold the line low, or a sensor that has failed to a low output. P0342 is a voltage-level fault — distinct from P0340 (no usable signal) and P0341 (signal present but out of spec).
What are the symptoms of P0342 on a 2017 Ford Mustang?
Check Engine Light is illuminated. Hard start with extended cranking. Possible complete no-start condition. Stalling, often when the engine is hot. Rough running and noticeably reduced power. Misfire-like stumbling if the ECM loses cylinder sync. Reduced fuel economy
What causes P0342 on a 2017 Ford Mustang?
Camshaft position sensor signal wire shorted to ground (most-common). Failed camshaft position sensor (output stuck low) (most-common). Corroded or water-intruded sensor connector (common). Oil leaking into the cam sensor port and shorting the sensor internals (common). Open or high-resistance reference-voltage or ground circuit feeding the sensor (occasional). Damaged or slipped camshaft reluctor / tone wheel (occasional). Failed PCM input for the cam sensor circuit (rare)
Is it safe to drive a 2017 Ford Mustang with P0342?
In most cases a 2017 Ford Mustang stays drivable for short trips with P0342 active, but it should be diagnosed and repaired promptly — this is a high-severity code. Ignoring it can lead to further damage or a failed emissions test.