P222D

Code

Generic P — Powertrain

Barometric Pressure Sensor B Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 23 EN: 37 RU: 25

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Short to battery voltage or to the 5V reference circuit on the sensor signal wire
Failed or damaged barometric pressure sensor (Sensor B)
Corroded/loose connector or damaged wiring harness (open/short/poor ground)
Incorrect sensor installation or aftermarket component causing interference
Internal ECU input circuit fault

Symptoms

Check Engine MIL illuminated
Engine may run rough, reduced drivability or enter limp mode on some vehicles
Failed emissions readiness or poor fuel economy
Stored or recurring diagnostic trouble codes related to pressure sensor circuits

What to check

Read and record freeze-frame and live data for Barometric Pressure Sensor B and related sensors
Compare Sensor B reading to Sensor A (if present) and to expected ambient barometric pressure
Visually inspect sensor, connector and wiring for damage, corrosion, or pinched sections
Backprobe signal, reference (usually 5V) and ground circuits at the sensor with key ON, engine OFF
Check for continuity/short to battery on the signal wire with power removed
Clear codes and retest after repairs; check for recurrence

Signal parameters

Typical reference supply: approximately 5 V (check vehicle spec)
Typical sensor output range: ~0.5 V to ~4.5 V across operating pressure range (varies by design)
Logic/high fault threshold often detected when signal is above ~4.5–4.8 V (specific threshold depends on manufacturer)
Expected signal at key ON, engine OFF: sensor should reflect ambient barometric pressure (non-saturated voltage within normal range)

Diagnostic algorithm

Retrieve all related codes and freeze-frame data with a scan tool. Note conditions when the code set.
Observe live data: compare Barometric Pressure Sensor B to Sensor A (if present) and to expected ambient pressure.
Visually inspect sensor, connector, and wiring for damage, corrosion, rodent damage or aftermarket taps.
With key ON (engine OFF), backprobe the sensor connector: verify 5V reference, ground continuity, and measure the signal voltage. If signal >4.5–4.8 V, suspect short to 5V or sensor fault.
With power off, check resistance/continuity between the signal wire and battery positive to find a short. Also check continuity to ECU pin and to ground.
Wiggle test the harness while monitoring live data to detect intermittent connections.
If wiring and connectors test good, swap Sensor B with a known-good/identical sensor (if available) or replace the sensor and recheck.
If code persists after sensor replacement and wiring verified, test or consult procedure for checking ECU input circuit; consider ECU repair/replacement only after exhausting wiring and sensor checks.
Clear codes and perform road/idle cycle to confirm repair and readiness status.

Likely causes

Signal wire shorted to 5V supply (or battery) due to chafing or pinched harness
Water ingress/corrosion at sensor connector producing high voltage reading
Sensor internal electronics failed and producing high output
Aftermarket device tapped into sensor circuit or reference supply
ECM input stage damaged (less common)

Fault status

⚠️ Status

Barometric Pressure Sensor B Circuit High — sensor signal voltage higher than expected. Check sensor, connector, wiring for short to 5V or sensor failure.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.5 hours