P14A8

Code

Generic P — Powertrain

Hybrid Battery Pack Temperature Sensor C Circuit Range/Performance

Brand: Generic

Type: P — Powertrain

Views: UK: 11 EN: 17 RU: 15

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Page language: EN

Causes

Open or short in the temperature sensor C wiring harness
Corroded, loose or damaged connector at the sensor or battery ECU
Failed temperature sensor (thermistor)
High‑resistance or lost ground / reference voltage to the sensor circuit
Battery pack control module (battery ECU/hybrid control module) input fault
Water intrusion or physical damage in the battery pack area

Symptoms

Hybrid system warning lamp or CHECK HYBRID/EV warning
Reduced battery charging, limited regeneration or reduced hybrid performance
Incorrect battery pack temperature reading for sensor C in scan tool
Possible limp mode or limited power operation
Fault may be intermittent or present under certain temperatures

What to check

Retrieve and record freeze frame and live data for battery temperature sensors using a capable scan tool.
Compare sensor C reading to other battery pack temperature sensors (A, B, D, etc.).
Perform visual inspection of the sensor C connector, wiring harness and battery pack entry points for damage, corrosion or moisture.
Check for proper reference voltage (typically ~5 V) and a good ground at the battery ECU harness connector with ignition on.
Backprobe sensor connector and measure signal voltage at rest and while warming/cooling the sensor (or while comparing to other sensors).
Measure sensor resistance with battery pack isolated (if safe and allowed) and compare to service specifications or expected thermistor behavior.

Signal parameters

Typical sensor type: thermistor (NTC) producing a variable voltage proportional to temperature.
Expected signal voltage range (typical): ~0.1–4.9 V depending on temperature and OEM circuit (verify spec for vehicle).
Reference/excitation commonly provided by the control module: ~5 V (verify on vehicle).
Resistance changes with temperature (NTC: resistance decreases as temperature increases).
Open circuit: signal may read fixed high or low voltage or show implausible temperature.
Short to ground: signal near 0 V; short to battery/5 V: signal near reference voltage.

Diagnostic algorithm

Safety first — follow all high‑voltage battery safety procedures and service manual instructions before working near the HV battery.
Clear codes, then recheck to confirm P14A8 returns and record freeze‑frame values and conditions.
Using a scan tool, monitor battery pack temperature sensors A–D (or all available) and note sensor C behavior compared to others and to ambient.
Visually inspect sensor C, its harness and connector at the pack for damage, corrosion or water intrusion.
With ignition ON (but high‑voltage system in safe state per manufacturer procedures), backprobe the sensor connector and check: a) reference/excitation voltage at the connector, b) signal voltage while varying temperature (warm by hand or cool) and c) ground continuity.
Isolate the sensor (disconnect) and measure sensor resistance across its terminals. Confirm resistance changes with temperature and matches OEM chart or that it behaves like an NTC thermistor (resistance falls as temperature rises).
Check continuity between the sensor connector and the battery/hybrid control module pins; check for shorts to battery positive and chassis ground.
If wiring, connector or terminal issues are found, repair or replace and retest. If wiring checks good and sensor resistance/voltage out of spec, replace the sensor.
If wiring and sensor test good, suspect module input fault — check module grounds/power and consider module diagnostics or replacement per manufacturer instructions.
After repairs, clear codes and perform a full system relearn or calibration if required, then road/test to confirm the fault does not return.

Likely causes

Damaged wiring or connector between sensor C and the battery/hybrid control module
Failed temperature sensor C (open or out-of-spec resistance)
Poor ground or missing 5 V reference to the sensor circuit

Fault status

⚠️ Status

Hybrid battery pack temperature sensor C circuit range/performance fault — sensor signal out of expected range (open/short/intermittent) or battery control module input not accepting valid temperature signal.

🔴 Repair difficulty: Hard

⏱️ Diagnostic time: 1-4 hours