P2E6E

Code

Generic P — Powertrain

Hybrid/EV Battery Pack “A” Cell Thickness Sensor Circuit Low

Brand: Generic

Type: P — Powertrain

Views: UK: 16 EN: 50 RU: 21

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Page language: EN

Causes

Damaged or shorted sensor wiring (short to ground)
Open circuit or high resistance in sensor wiring/connectors
Corroded, loose, or contaminated connector at sensor or BMS harness
Faulty cell thickness sensor module or sensor element
Battery pack high-voltage isolation or interconnect issue affecting the sensor circuit
Battery management system (BMS) or module internal fault or software/calibration error

Symptoms

Battery pack warning lamp or hybrid/EV malfunction indicator illuminated
Reduced battery performance, derating of charge/discharge, or limp/heal-back mode
Pack unable to enter EV mode or reduced available battery capacity
Logged fault present in scan tool and possibly stored freeze-frame data
Intermittent faults correlated with vibration, temperature changes, or connector movement

What to check

Use an OBD/scan tool to read P2E6E and any related codes; record freeze-frame/live data values
Verify the vehicle is de-powered and follow manufacturer high-voltage safety procedures before touching the traction battery
Visually inspect sensor harness and connectors for damage, corrosion, pin push-out, chafing or signs of repair
Check for service bulletins or software updates related to cell sensor/BMS
Backprobe the sensor connector (with HV system made safe) and observe supply/reference and signal lines using a multimeter or appropriate diagnostic tool
Perform continuity and short-to-ground checks on the sensor wiring (insulation resistance where specified)

Signal parameters

Typical sensor circuit uses a low-voltage reference/supply and a signal return (example reference: 5.0 V supply; signal expected ~0.5–4.5 V under normal conditions) — manufacturer specifications required for exact values
Condition that triggers code: signal voltage below manufacturer threshold (typical trigger < ~0.5 V) or signal pinned near ground
If open circuit: infinite/very high resistance on continuity check. If shorted: near 0 Ω to chassis ground or to supply ground

Diagnostic algorithm

Read and record all stored codes and freeze-frame data with a compatible scan tool; note related battery or BMS codes.
Follow manufacturer prescribed high-voltage isolation and PPE procedures before performing any physical checks on the traction battery.
Perform a visual inspection of the battery pack area, sensor harness, and connectors for damage, corrosion, pin damage or evidence of previous work.
With the system made safe per procedure, disconnect the sensor connector and inspect pins for corrosion, bending, or contamination. Reconnect and wiggle harness to check for intermittent behavior.
Backprobe the sensor harness at the connector (or at the BMS input if directed by service manual) and measure reference supply and signal voltage with the pack made safe as required by procedures; compare to spec. Look for low signal or loss of reference supply.
Check continuity between the sensor signal wire and the BMS input; check for shorts to chassis ground on the signal line and supply line.
If wiring checks are OK, test or replace the cell thickness sensor/module per service manual procedures. Some tests require removal of pack or module and must be performed by qualified technicians.
If sensor and wiring test good, suspect BMS input circuit failure or software/calibration issue — check for TSBs, reprogram BMS if update available, or perform module replacement diagnostics per OEM procedures.
Clear codes, perform functional tests or controlled charge/discharge cycles as directed, and road- or cycle-test while monitoring live data for recurrence.
If intermittent or unresolved, escalate to specialist with access to full pack diagnostic equipment and manufacturer repair information.

Likely causes

Wiring short to ground between sensor and BMS
Connector corrosion or poor mating at the cell sensor plug
Failed cell thickness sensor element or module within pack
Internal BMS input circuit failure or blown reference supply

Fault status

⚠️ Status

Hybrid/EV Battery Pack “A” Cell Thickness Sensor Circuit Low — BMS detects signal below expected threshold (possible short to ground, open circuit, or faulty sensor).

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0 - 3.0 hours