Air intakeGeneric OBD-II codeUrgency: Garage soon
Code P0110: intake air temperature (IAT) sensor: circuit fault
P0110 means: intake air temperature circuit: malfunction.[1][2] The engine ECU has detected a fault in the intake air temperature (IAT) sensor circuit, the part that reports the temperature of the air entering the engine, or in its electrical connections. The ECU uses this reading to calculate the air-fuel mixture and to adjust the ignition timing, so with a wrong reading the engine may run worse. Mechanic Base describes it as an absence of signal from the sensor.[1][2][3][4]
What code P0110 means
The engine ECU has detected a fault in the intake air temperature (IAT) sensor circuit, the part that reports the temperature of the air entering the engine, or in its electrical connections. The ECU uses this reading to calculate the air-fuel mixture and to adjust the ignition timing, so with a wrong reading the engine may run worse. Mechanic Base describes it as an absence of signal from the sensor.[1][2][3][4]
While the fault lasts, the ECU cannot use the real temperature and works with an estimated or substitute value: Mechanic Base talks about estimated values, and the Saab manuals give 20 °C on a 1998 9-3 with EDC 15 and 40 °C on a 2005 9-3 (EDC16). On many cars this sensor is built into the air flow meter or into a combined manifold pressure and temperature sensor.[3][4][5][6][7]
It is the general warning for the intake air temperature sensor, alongside codes P0112 and P0113, but each manufacturer applies it in its own way. In the Saab manual for the 1996 900, P0110 is a general code and P0112 and P0113 correspond to a sensor voltage that is too low or too high; in contrast, in the manuals for the 1998 9-3 (EDC 15) and 2005 9-3 (EDC16) it is described as a short to positive or an open circuit, and on the first the diagnostic tool reads −50 °C.[5][6][8]
It is a generic OBD-II code (it starts with P0), not specific to one brand, so its definition is the same on any car; what changes from one engine to another is the most likely cause.[9]
Original definition (SAE J2012): Intake Air Temperature Circuit Malfunction[1][2]
Causes of P0110
From most to least likely, according to the sources.
- 1Faulty IAT sensor.[1][3][10]
- 2Sensor wiring and connectors in poor condition: damaged, broken or interrupted wires, connector loose, oxidised or with pushed-in terminals, short circuit or interrupted power supply.[1][3][6][10]
- 3If the sensor is built into the air flow meter or into a combined pressure and temperature sensor, the fault may be in that part.[4][7]
- 4Faulty engine ECU: the sources leave it for last, when everything else has been ruled out.[1][3][10]
- 5Dirty or blocked air filter: Autodoc includes it in its list, although it does not explain how it would affect the sensor circuit.[1]
Symptoms
- Engine warning light (check engine light) on in the instrument cluster; according to Mechanic Base, in most cases it is the only symptom.[1][3][10]Engine warning light: faults that cause it
- Hard or erratic starting, especially from cold.[1][4][10]Hard to start: faults that cause it
- Less power and poorer acceleration.[1][4][10]Less power: faults that cause it
- Rough idle.[1][3][4][10]Vibrations: faults that cause it
- Increased fuel consumption.[1][3][4][10]Uses more fuel: faults that cause it
- Black smoke from the exhaust.[1]Black smoke: faults that cause it
How to diagnose P0110
In order: from the most likely and cheapest to check to the most expensive.
- 1With a diagnostic tool, read the code and the intake air temperature in the live data. It should be close to the ambient temperature (Mechanic Base gives about 10 degrees either way, depending on the outside and engine temperature); an absurd reading, such as the −50 °C that the Saab manual mentions for the EDC 15, points to an open circuit or a short circuit.[3][4][5]
- 2Disconnect the sensor and inspect the connector (corrosion, oxidation, pushed-in terminals or terminals with low contact pressure) and visually check the wires.[3][6]
- 3Wiggle the wiring loom at several points and in several directions while watching the reading, to detect intermittent breaks or short circuits.[6]
- 4Measure the sensor's resistance between its terminals and compare it with the manufacturer's specification (it varies with temperature), and check the continuity of the supply and signal wires to the ECU.[3][4][10]
- 5Check the ECU input: in the Saab manual for the 1996 900, with the sensor disconnected the reading should go to about −40 °C and, with a jumper between the two terminals, to about +123 °C.[8]
- 6If the sensor is open or out of specification, replace it (or the part that contains it, if it is an assembly); if the wiring is damaged, repair it and clean the connector. The ECU is checked last.[1][3][4]
Can I keep driving with P0110?
Garage soon
No source presents it as a safety risk: Autodoc says that, as a rule, driving safety is not in immediate danger and Mechanic Base classes it as low severity, with the warning light the only symptom in most cases. Even so, the sources do not entirely agree: Autodoc asks for it to be corrected promptly because it can increase consumption and damage the engine, and Mechanic Base recommends taking the car to a mechanic as soon as possible if you do not know how to diagnose the sensor. In the meantime, the ECU works with a substitute temperature value.[1][3][4][5][6]
Documented faults related to P0110
Known faults of specific engines and cars, with their repair cost, the affected years and their sources.
Engine sensors: the most serious faults by engine and car
- High severityFrequency: Occasional2.0 DTI and 2.2 DTIVP44 injection pump and air mass meter failureGerman Wikipedia documents recurring failures of the Bosch VP44 injection pump and the air mass meter in the early years of this engine. An owner testimony for this engine describes the pump being replaced at 192,500 km, at a cost the owner calls «prohibitive».
- Medium severityFrequency: Common2.0 TDIClogged particulate filter or faulty pressure sensorThe 2.0 TDI's particulate filter clogs if the car mostly makes short journeys, because it never gets to regenerate; sometimes the fault is just the differential pressure sensor. Cleaning it costs around €200 and replacing it, €800 to €3,000.Repair (garage): €800–€3,000
- Medium severityFrequency: Common1.4 and 1.6 8vCrankshaft position sensor failure (TDC sensor)The crankshaft position sensor (capteur PMH, or TDC sensor) appears repeatedly in the reliability sources for the Clio II, the Kangoo I and the Dacia Logan I with this engine, with hard cold starting or stalling as the main symptoms. It is a cheap part, but the failure can leave you stranded.
- Medium severityFrequency: Common1.4 and 1.6 16vCrankshaft position sensor failureThe crankshaft position sensor (capteur PMH) appears repeatedly in the reliability sources for almost every generation with this engine, with hard cold starting, stalling or the car cutting out unexpectedly. It is a cheap part, but the failure can leave you stranded.
Wiring, connectors and short circuits: the most serious faults by engine and car
- Critical severityFrequency: OccasionalBMW N62 / N63Additional turbo coolant pump with a risk of short circuit and fireIn 2011 BMW recalled 5, 6 and 7 Series, X5 and X6 models built between 2007 and 2011 because of the additional turbo coolant pump: moisture, a short circuit and, in extreme cases, a fire. In 2012 there was another campaign for a crack in the pump, with a more robust version.
- High severityFrequency: Occasional1.3 TCeBlown fuel pump fuseOn the Renault Captur II and Clio V with the 1.3 TCe engine, a 20-amp fuse can blow and leave the car without an engine. According to L'argus, in April 2021 this fault still had no factory fix; the official service centre's diagnosis includes checking, and sometimes replacing, the catalytic converter.
- High severityFrequency: OccasionalM264/M254Poorly tightened 48 V earth wiring in the mild-hybrid system (fire risk)Mercedes-Benz has issued several recalls (2022-2025) because the 12 V and 48 V earth connections of some cars with a 48 V system may be poorly tightened: resistance rises, the connection heats up and a fire cannot be ruled out. The official workshop checks them and repairs them if necessary in an hour or more.
- High severityFrequency: Occasional1.9 TDIUnit injector tappet wear and injector wiring damageOn the unit injector system, the tappets that operate the injectors can wear if the oil is not changed on time, and the injector wiring can be damaged by contact with oil, causing misfires or loss of power.
- Critical severityFrequency: CommonRover 75Seat SRS connector fault with airbag and seatbelt warning light onAuto Express warns that the Rover 75's seat SRS connector can cause the airbags to fail, and dealers were fixing it with revised connectors. The Dutch APK inspection puts the airbag or seatbelt fault warning among the most frequent defects across almost all series.
- Critical severityFrequency: OccasionalAlfa Romeo GiuliettaShort circuit from badly routed wiring that can prevent gear shifting (KBA campaign, 2010-2015)Yes: according to Germany's KBA, on Alfa Romeo Giulietta cars built between 2010 and 2015 inadequate cable routing could cause a short circuit and, as a result, gear-shift failure.
Frequently asked questions
Can I drive with code P0110?
Normally yes, at least to get to the garage: Autodoc says short distances can be covered and that, as a rule, driving safety is not in immediate danger, and Mechanic Base classes it as low severity. That said, Autodoc asks for it to be corrected promptly because it can increase consumption and damage the engine.[1][3]
What is the difference between P0110 and P0112 and P0113?
P0110 is the warning for a fault in the intake air temperature sensor circuit, and the neighbouring codes narrow the problem down. In the Saab manual for the 1996 900, P0110 is a general code, P0112 is set when the sensor voltage is too low (less than 0.06 V for 5 seconds) and P0113 when it is too high (more than 4.96 V for 5 seconds). Not all manufacturers apply it in the same way: on the 1998 9-3 with EDC 15, P0110 is a short to positive or an open circuit (more than 4.7 V for 0.6 seconds) and P0111 is the short to ground.[5][8]
Do I have to replace the air flow meter when P0110 appears?
Only if the temperature sensor is built into it, which according to Mechanic Base is common, and the tests point to that part. First it is worth checking the connector and wiring, which are the most repeated causes in the sources. Pico also explains that combined manifold pressure and temperature sensors exist.[1][4][7][10]
How is P0110 diagnosed?
With the diagnostic tool, the intake air temperature is read and compared with the ambient temperature; then the sensor, connector and wiring are inspected (wiggling the loom to detect intermittent faults), the sensor's resistance and the continuity of the wires are measured and, only if everything is fine, the sensor is replaced or the ECU is checked.[3][4][6][10]
Does P0110 mean the same on all brands?
The official definition is the same, because codes starting with P0 are generic OBD-II codes, but each manufacturer applies it in its own way: the Saab manuals treat it as a general code (1996 900) or as a short to positive or an open circuit (1998 and 2005 9-3), with different substitute values, of 20 °C and 40 °C.[5][6][8][9]
Will I pass the MOT with code P0110?
If the code has switched on the engine warning light, no: with that light on, the inspection records a serious defect, and on Euro 5 and Euro 6 cars the ITV (Spain's roadworthiness inspection, similar to the MOT) also reads the OBD diagnostic system. Repair the fault before you go; clearing the code just before the inspection does not help either, because it counts as a serious defect.[11]
Not sure what is wrong with your car? Describe what you notice in the symptom diagnosis or see all fault codes.
Sources
Every fact on this page links to its source. If you find an error, let us know.
- Código OBD2 P0110: causas, síntomas y cómo corregirloAutodoc Club · Technical documentation · consulted 2 October 2026 · in Spanish
- P0110 — Intake Air Temperature Circuit MalfunctionThe Automotive Technician (TaT) · Technical documentation · consulted 2 October 2026
- P0110 Code - Meaning, Causes, Symptoms (& How To Fix It)Mechanic Base · Technical documentation · published 11 February 2023 · consulted 2 October 2026
- 7 Signs Your Intake Air Temperature (IAT) Sensor Is BadMechanic Base · Other source · published 12 February 2023 · consulted 2 October 2026
- Saab 9-3 (9400) 1998, EDC 15: P0110 Intake Air Temperature Sensor Circuit. Short to B+ / Open Circuit; P0111 Short to Ground.Saab Workshop Information System (WIS Online) (copia del manual de taller de Saab) · Technical documentation · consulted 2 October 2026
- Saab 9-3 (9440) 2005, EDC16: P0110 11 Intake Air Temperature Sensor Circuit. Short to B+ / Open Circuit.Saab Workshop Information System (WIS Online) (copia del manual de taller de Saab) · Technical documentation · consulted 2 October 2026
- MAP and temperature (turbo diesel) | Automotive oscilloscope testPico Technology · Technical documentation · consulted 2 October 2026
- Saab 900 1996, Trionic OBD-II: P0110, P0112, P0113 Intake Air Temperature SensorSaab Workshop Information System (WIS Online) (copia del manual de taller de Saab) · Technical documentation · consulted 2 October 2026
- On-board diagnosticsWikipedia · Other source · consulted 2 October 2026
- OBD Fehlercode P0110 | AnsauglufttemperatursensorCarWiki.de · Technical documentation · consulted 2 October 2026 · in German
- Desmontando mitos: ¿puede pasar mi coche la ITV con el testigo de «avería motor» encendido?Diariomotor · Motoring press · published 8 March 2021 · consulted 2 October 2026 · in Spanish