P0117 on Volkswagen
Engine Coolant Temperature Sensor Circuit Low
P0117 on Volkswagen vehicles indicates engine coolant temperature sensor circuit low. Au7o has documented this code across 2 Volkswagen models — most commonly on Golf R, New Beetle. This code means the engine coolant temperature (ECT) sensor is reading too low a voltage, which the computer interprets as an impossibly high coolant temperature. In most cases this is an electrical fault — such as a short to ground in the wiring — rather than the engine actually overheating. The coolant temperature signal affects fuel mixture, cooling fans, and other functions, so a bad reading can cause poor running, hard starting, or fans running constantly. The fault is usually in the sensor or its wiring. Typical repair costs on Volkswagen range from $30 to $300, depending on the specific model and root cause.
Common Causes of P0117
- •Faulty engine coolant temperature sensor
- •Short to ground in the sensor signal wire
- •Damaged or corroded wiring/connector at the sensor
- •Coolant contamination affecting the sensor
- •Poor electrical ground
- •Faulty PCM/ECM (less common)
P0117 on Volkswagen by Model
Volkswagen Golf R(1 issue)
- Engine Coolant Temperature Sensor / Inaccurate Temp Gauge2015-2021
Separate from the well-known water-pump/thermostat-housing leak, MK7-platform Golf R owners report failures of the engine coolant temperature (ECT) sensor and a notably unreliable dashboard temperature gauge. The gauge tends to sit pinned at ~90C and gives little warning before overheating, so coolant loss or a failing sensor can let the engine run dangerously hot without alerting the driver. A faulty ECT sensor also causes erratic readings, false overheat warnings, poor cold-start fueling/economy, and a check engine light. VW updated early sensor revisions.
Volkswagen New Beetle(1 issue)
- Engine Coolant Temperature Sensor (G62) Failure1998-2006
The early black-topped coolant temperature sensor (G62, often on the coolant flange below the upper radiator hose) is a well-known weak point on the 2.0 8V and 1.8T New Beetle. The plastic sensor and its flange crack or the sensor sends erratic readings, causing the temperature gauge to swing or read falsely hot/cold, hard cold starts and rich/lean running, and a check-engine light. The original black sensor was superseded by an updated green sensor. Because the ECU uses this signal for fueling and fan control, a failed sensor can mimic a thermostat or head-gasket problem and trigger unnecessary repairs.
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View P0117 across all makes →Frequently Asked Questions
What does P0117 mean on Volkswagen?▼
P0117 stands for "Engine Coolant Temperature Sensor Circuit Low." This code means the engine coolant temperature (ECT) sensor is reading too low a voltage, which the computer interprets as an impossibly high coolant temperature. In most cases this is an electrical fault — such as a short to ground in the wiring — rather than the engine actually overheating. The coolant temperature signal affects fuel mixture, cooling fans, and other functions, so a bad reading can cause poor running, hard starting, or fans running constantly. The fault is usually in the sensor or its wiring. On Volkswagen specifically, this code is documented across 2 models.
What causes P0117 on Volkswagen vehicles?▼
Common causes on Volkswagen: Faulty engine coolant temperature sensor, Short to ground in the sensor signal wire, Damaged or corroded wiring/connector at the sensor, Coolant contamination affecting the sensor, Poor electrical ground. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0117 on a Volkswagen?▼
Repair costs on Volkswagen range from $30 to $300, depending on the specific model and root cause.
Which Volkswagen models have P0117 documented?▼
Au7o has documented P0117 on 2 Volkswagen models: Golf R, New Beetle.