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DTC/P0117

P0117 : Engine Coolant Temperature (ECT) Circuit Low

Quick Answer
Moderee GraviteConduite possible (a court terme)Systeme de refroidissement

P0117 means the engine coolant temperature (ECT) sensor circuit voltage is too low, which the ECU reads as an implausibly high temperature. Because the sensor is a thermistor whose resistance falls as it heats, a short to ground or a shorted sensor produces a low voltage that mimics extreme heat. The ECU often responds by running the cooling fan at full speed. Repair typically costs 40 to 180 EUR for a sensor or wiring fix.

Cout de reparation estimeDe 12 € a 190 €+, varie selon le vehicule

Que signifie P0117 ?

P0117 means the engine coolant temperature (ECT) sensor circuit voltage is too low, which the ECU reads as an implausibly high temperature. Because the sensor is a thermistor whose resistance falls as it heats, a short to ground or a shorted sensor produces a low voltage that mimics extreme heat. The ECU often responds by running the cooling fan at full speed. Repair typically costs 40 to 180 EUR for a sensor or wiring fix.

P0117 est un code defaut lie a systeme de refroidissement, classe en gravite moderate. Lorsque le calculateur de ton vehicule detecte cette condition, il enregistre P0117 et allume le voyant moteur.

Quels sont les symptomes de P0117 ?

Si ton vehicule a declenche P0117, tu peux remarquer un ou plusieurs de ces symptomes :

  • Check engine light illuminated
  • Temperature gauge reading very high or pinned
  • Cooling fan running constantly at high speed
  • Lean fuelling and possible hesitation
  • Hard starting if the ECU thinks the engine is already hot
  • Reduced fuel economy

Quelles sont les causes de P0117 ?

Voici les causes les plus courantes de P0117, classees selon la probabilite qu'elles soient en cause :

eleveeCoolant temperature sensor shorted internally (low resistance)
eleveeSignal wire shorted to ground
moyenneCorroded connector bridging the sensor terminals
moyenneChafed harness shorting the signal to chassis
faibleWrong sensor fitted with incorrect resistance curve
faibleECU internal fault on the sensor input (rare)

Peut-on rouler sans risque avec P0117 ?

En general oui, pour des trajets courts. Usually safe to drive short distances. P0117 means the coolant sensor signal voltage is too low, which the ECU interprets as an implausibly hot engine (a low-resistance short reads as high temperature). This can force the cooling fan to run at full speed and lean out fuelling, hurting economy. Because the gauge may show a false high reading, confirm the real temperature in live data and fix the fault promptly so you do not mask genuine overheating.

Comment diagnostique-t-on P0117 ?

Suis ces etapes pour identifier la cause profonde de P0117 :

  1. Read the code and watch the live coolant temperature PID with Skanyx. P0117 typically shows the maximum value (often around 120 C or higher) even on a cold engine, which is a clear sign of a low-voltage short rather than a real overheat
  2. Compare the live coolant reading against actual engine temperature by touching the upper radiator hose; if the engine is cold but the PID reads hot, the circuit is shorted
  3. Unplug the sensor connector and check whether the reading drops to the open-circuit default; if it does, the sensor itself is likely shorted internally
  4. Inspect the connector and harness for corrosion, moisture, or a chafe point shorting the signal wire to ground or to the sensor body
  5. Measure the sensor resistance with a multimeter and compare to the manufacturer table; an abnormally low resistance confirms a failed sensor
  6. If the sensor and connector are good, test the signal wire for a short to ground back toward the ECU

Combien coute la reparation de P0117 ?

Les couts de reparation de P0117 varient selon la cause profonde et ton vehicule. Voici des estimations courantes :

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace coolant temperature sensor (DIY) €12–€45 €0–€0 €12–€45 Facile
Replace coolant temperature sensor (shop) €12–€45 €40–€100 €52–€145 Facile
Repair shorted wiring or connector €5–€30 €60–€160 €65–€190 Moderee
Diagnose short to ground (shop) €0–€0 €60–€120 €60–€120 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

P0117 sur des vehicules specifiques

P0117 se comporte differemment selon ton vehicule. Selectionne ta voiture ci-dessous pour des causes propres au modele, les problemes connus et des estimations de couts ajustees :

Toyota

P0117 sur Toyota Corolla

2005-2024

On the Corolla, P0117 most often comes from a shorted sensor or moisture-induced corrosion bridging the connector terminals. The sensor is inexpensive and easy to reach, so confirm with live data and a resistance check before replacing.

Quelles sont les causes de P0117 sur une Toyota Corolla ?

Toyota CorollaInternally shorted thermistor reading maximum temperature
Toyota CorollaConnector corrosion bridging the signal and ground pins

Cout de reparation de P0117 pour Toyota Corolla

Couts estimes pour les proprietaires de Toyota Corollaajuste a la baisse par rapport a la moyenne en raison du prix des pieces specifiques a Toyota

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace coolant temperature sensor (DIY) €11–€41 €0–€0 €11–€41 Facile
Replace coolant temperature sensor (shop) €11–€41 €36–€90 €47–€131 Facile
Repair shorted wiring or connector €5–€27 €54–€144 €59–€171 Moderee
Diagnose short to ground (shop) €0–€0 €54–€108 €54–€108 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

Volkswagen

P0117 sur Volkswagen Golf

2005-2024

VW Golf combined coolant sensors can fail internally and short, producing a pinned-high reading. Connector and clip damage is also common on these sensors, so inspect the four-pin plug for moisture and a secure fit.

Quelles sont les causes de P0117 sur une Volkswagen Golf ?

Volkswagen GolfInternally shorted combined coolant sensor
Volkswagen GolfMoisture in the four-pin connector shorting the signal
BMW

P0117 sur BMW 3 Series

2006-2024

On BMW 3 Series engines a shorted coolant sensor will trigger the cooling fan to run at full speed, which is often the owner's first clue. Connector fretting and harness chafing near the engine are worth inspecting before replacing the sensor.

Quelles sont les causes de P0117 sur une BMW 3 Series ?

BMW 3 SeriesShorted coolant sensor driving the fan to maximum
BMW 3 SeriesHarness chafe shorting the signal wire to ground

Cout de reparation de P0117 pour BMW 3 Series

Couts estimes pour les proprietaires de BMW 3 Seriesajuste a la hausse par rapport a la moyenne en raison du prix des pieces specifiques a BMW

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace coolant temperature sensor (DIY) €16–€59 €0–€0 €16–€59 Facile
Replace coolant temperature sensor (shop) €16–€59 €52–€130 €68–€189 Facile
Repair shorted wiring or connector €7–€39 €78–€208 €85–€247 Moderee
Diagnose short to ground (shop) €0–€0 €78–€156 €78–€156 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

Ford

P0117 sur Ford Focus

2005-2024

The Ford Focus can set P0117 from a shorted sensor or from a chafed harness near the engine, where insulation rubs through and grounds the signal wire. Inspect the pigtail for heat and abrasion damage before condemning the sensor.

Quelles sont les causes de P0117 sur une Ford Focus ?

Ford FocusShorted coolant temperature sensor
Ford FocusChafed harness grounding the signal wire near the engine

Cout de reparation de P0117 pour Ford Focus

Couts estimes pour les proprietaires de Ford Focusajuste a la baisse par rapport a la moyenne en raison du prix des pieces specifiques a Ford

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace coolant temperature sensor (DIY) €11–€43 €0–€0 €11–€43 Facile
Replace coolant temperature sensor (shop) €11–€43 €38–€95 €49–€138 Facile
Repair shorted wiring or connector €5–€29 €57–€152 €62–€181 Moderee
Diagnose short to ground (shop) €0–€0 €57–€114 €57–€114 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

Ces codes apparaissent souvent avec P0117 ou indiquent des problemes connexes :

Questions frequentes sur P0117

Why does P0117 make the gauge read hot when the engine is cold?

The coolant sensor is a thermistor whose resistance drops as it gets hotter, so a low signal voltage looks identical to a very hot engine. When the circuit shorts to ground, the voltage drops to near zero and the ECU interprets that as maximum temperature, even on a stone-cold engine.

Can I drive with P0117?

For short trips usually yes, but be careful. The ECU thinks the engine is overheating, so it may run the fan flat out and lean the mixture, hurting economy. The real danger is that a false high reading hides genuine overheating, so confirm actual temperature in live data and fix it soon.

Is P0117 the sensor or the wiring?

It can be either. A shorted thermistor inside the sensor is common and easy to confirm by unplugging the connector and checking whether the reading changes. If unplugging does not clear the implausible reading, suspect a signal wire shorted to ground in the harness.

How much does it cost to fix P0117?

If a shorted sensor is the cause, parts are usually 12 to 45 EUR and a DIY swap can be under 50 EUR. A shop sensor replacement runs roughly 60 to 150 EUR. Chasing a wiring short costs more because diagnostic labour is involved.

Lis nos guides detailles

Skanyx

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