What is the function of Coolant Temperature Sensors and How to test, remove, and install it on Volvo 740?

The Engine Coolant Temperature (ECT) sensor contains a resistance that changes with the engine coolant temperature, decreasing as the temperature increases and increasing as it decreases, giving a reference signal to the ECM that is related to the coolant temperature. This signal is used by the ECM to determine spark advance, E6R flow rate, air/fuel ratio and to determine engine temperature while also facilitating the operation of the temperature gauge by sending a signal to the instrument cluster. To test the sensor, set the key to the ON position with the engine OFF, measure the resistance across the terminals of the sensor and compare it to a reference chart to determine whether it is within specifications if not replace. For removal and installation, you first need to disconnect the negative battery cable - always take care to avoid any service to the radiator and cooling system when it is hot to avoid getting burns and risk of possible damage to pets from the ethylene glycol content - antifreeze. Drain the engine coolant and recycle, remove the parts that are blocking access to the sensor, disconnect the sensor, and unscrew it with the appropriate socket. To install, insert the new sensor in its mounting position and tighten it, reconnect the sensor, reconnect any parts that are removed, refill and bleed the cooling system, reconnect the negative battery cable, and finally check for any leaks.

How to replace coolant temperature sensors on Volvo V70?

The coolant temperature sensor in the thermostat housing is used as an engine temperature source signal for the engine management system and the instrument panel temperature gauge. If a fault occurs in the sensor, or if there is a loss of signal because of poor electrical connections a fault code is logged in the engine management system ECU which can be accessed via the diagnostic connector in the centre console using a suitable fault code reader. In the event of a logged fault code, it is important to check the sensor wiring and connector carefully and while testing by substitution with a new unit is an option, further checks should be made using Volvo test equipment by a dealer or a suitably equipped specialist. To start removal, partially drain the cooling system down to just below the level of the sensor unit which is about 2.0 litres. For petrol models up to 2001, remove the two Torx bolts and lift off the thermostat housing cover and disconnect the wiring at the adjacent connector, and unscrew the sensor out of its position in the thermostat housing. For petrol models from 2002, remove the upper timing belt cover by undoing the clips or screws, disconnect the sensor wiring plug and then remove the sensor from the thermostat housing, removing the sensor seal if fitted and making sure to use a new one. For diesel models, pull the plastic cover on top of the engine straight up and disconnect the wiring plug before unscrewing the sensor from the housing, also discard the seal if fitted and replace it with a new one. When refitting, screw in the new sensor unit with a smear of sealant on the threads or new seal as applicable and reconnect the wiring connector and reassemble the thermostat housing making sure the screws are tightened securely. Finally, reconnect radiator hose or re-fit timing belt cover or engine cover as required and top up coolant level as required.

Genuine Volvo Coolant Temperature Sensors

Coolant Temperature Sensor

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16 Coolant Temperature Sensors found

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Volvo Coolant Temperature Sensor Part Number: 30646713
$28.12 MSRP: $36.02
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Product Specifications
- Other Name: IAT Sensor; Engine Coolant Temperature Sensor
Fits the following Volvo Models:
- S80 | 2007-2010 | V8 | 8 Cyl 4.4 L GAS
- XC90 | 2006-2011 | V8, V8 Ocean Race, V8 Sport | 8 Cyl 4.4 L GAS
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Volvo Coolant Temperature Sensor Part Number: 8653103
$28.12 MSRP: $36.02
You Save: $7.90 (22%)
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Product Specifications
- Other Name: IAT Sensor; Coolant Temperature Sensor
Fits the following Volvo Models:
- C70 | 2002-2004 | Base | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- S60 | 2002-2009 | 2.4, 2.4T, 2.5T, 2.5T AWD, AWD, Base, R, T5 | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS, 5 Cyl 2.5 L GAS
- S80 | 2005-2006 | 2.5T, 2.5T AWD | 5 Cyl 2.5 L GAS
- V70 | 2002-2007 | 2.4, 2.4T, 2.5T, 2.5T AWD, AWD, Base, R, T5 | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS, 5 Cyl 2.5 L GAS
- XC70 | 2003-2007 | Base, Ocean Race, X/C | 5 Cyl 2.5 L GAS
- XC90 | 2003-2006 | 2.5T, Base | 5 Cyl 2.5 L GAS
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Volvo Coolant Temperature Sensor Part Number: 8627679
$42.20 MSRP: $54.04
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Product Specifications
- Other Name: IAT Sensor; Engine Coolant Temperature Sensor
Fits the following Volvo Models:
- S80 | 2001-2005 | 2.9, T6, T6 Premier | 6 Cyl 2.8 L GAS, 6 Cyl 2.9 L GAS
- XC90 | 2003-2005 | 2.5T, Base, T6 | 5 Cyl 2.5 L GAS, 6 Cyl 2.9 L GAS
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Volvo Coolant Temperature Sensor Part Number: 30750926
$43.94 MSRP: $65.49
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Product Specifications
- Other Name: Temperature Gauge; Coolant Temperature Sensors; Coolant Temperature Sensor, Temperature Sensor
Fits the following Volvo Models:
- S60 | 2011-2016 | T6, T6 Polestar, T6 R-Design, T6 R-Design Platinum | 6 Cyl 3.0 L GAS
- S80 | 2007-2015 | 3.2, T6 | 6 Cyl 3.0 L GAS, 6 Cyl 3.2 L GAS
- V60 | 2015-2016 | T6 Polestar, T6 R-Design, T6 R-Design Platinum | 6 Cyl 3.0 L GAS
- XC60 | 2010-2013 | 3.2, 3.2 R-Design, T6, T6 R-Design | 6 Cyl 3.0 L GAS, 6 Cyl 3.2 L GAS
- XC90 | 2007-2014 | 3.2, 3.2 R-Design | 6 Cyl 3.2 L GAS
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Volvo Temperature Sensor Part Number: 31368969
$47.32 MSRP: $70.53
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Product Specifications
- Other Name: Coolant Temperature Sensors; Temperature Sensor
Fits the following Volvo Models:
- S60 | 2019-2023 | Recharge R-Design, T8 Inscription, T8 Polestar, T8 R-Design, T8 Recharge Core, T8 Recharge Inscription, T8 Recharge Plus, T8 Recharge Polestar, T8 Recharge R-Design, T8 Recharge R-Design Expression, T8 Recharge Ultimate | 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
- V60 | 2020-2023 | T5 Inscription, T5 Momentum, T5 R-Design, T6 Inscription, T6 Momentum, T6 R-Design, T8 Polestar, T8 Recharge Polestar | 4 Cyl 2.0 L GAS, 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
- XC60 | 2018-2023 | T8 Inscription, T8 Momentum, T8 Polestar, T8 R-Design, T8 Recharge Core, T8 Recharge Inscription, T8 Recharge Inscription Expression, T8 Recharge Plus, T8 Recharge Polestar, T8 Recharge R-Design, T8 Recharge Ultimate | 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
- XC90 | 2016-2023 | T8 Inscription, T8 Momentum, T8 R-Design, T8 Recharge Core, T8 Recharge Inscription, T8 Recharge Inscription Expression, T8 Recharge Plus, T8 Recharge R-Design, T8 Recharge Ultimate | 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
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Volvo Temperature Sensor Part Number: 30668640
$25.91 MSRP: $33.18
You Save: $7.27 (22%)
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Product Specifications
- Other Name: Coolant Temperature Sensors; Temperature Sensor
Fits the following Volvo Models:
- S60 | 2022-2023 | B5 Core, B5 Inscription, B5 Momentum, B5 Plus, B5 R-Design, B5 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- S90 | 2022-2023 | B6 Inscription, B6 Momentum, B6 Plus, B6 R-Design, B6 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- V90 Cross Country | 2022-2023 | B6, B6 Plus, B6 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- XC40 | 2023 | B4 Plus, B4 Ultimate, B5 Core, B5 Plus, B5 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- XC90 | 2023 | B5 Core, B5 Plus, B6 Core, B6 Plus, B6 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
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Volvo Coolant Temperature Sensor Part Number: 30668661
$29.04 MSRP: $37.18
You Save: $8.14 (22%)
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Product Specifications
- Other Name: Temperature Sensor; Coolant Temperature Sensors; Coolant Temperature Sensor, Temperature Sensor
Fits the following Volvo Models:
- C40 Recharge | 2022 | Ultimate | BATTERY EV (EV/BEV)
- S60 | 2022 | B5 Inscription, B5 Momentum | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- S90 | 2022-2023 | B6 Inscription, B6 Momentum, B6 Plus, B6 R-Design, B6 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- V60 Cross Country | 2023, 2020-2021 | B5 Plus, B5 Ultimate, T5 | 4 Cyl 2.0 L GAS, 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- V90 Cross Country | 2022-2023 | B6, B6 Plus, B6 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- XC40 | 2023 | B4 Plus, B4 Ultimate, B5 Core, B5 Plus, B5 Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV)
- XC90 | 2023 | B5 Core, B5 Plus, B6 Core, B6 Plus, B6 Ultimate, T8 Recharge Core, T8 Recharge Plus, T8 Recharge Ultimate | 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV), 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
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Volvo Coolant Temperature Sensor Part Number: 31339941
$29.04 MSRP: $37.18
You Save: $8.14 (22%)
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Product Specifications
- Other Name: Coolant Temp Sensor; Coolant Temperature Sensor, Temperature Sensor
Fits the following Volvo Models:
- S60 | 2015-2023 | Polestar, Recharge R-Design, T5, T5 Dynamic, T5 Inscription, T5 Inscription Platinum, T5 Inscription Premier, T5 Momentum, T5 Platinum, T5 Premier, T5 Premier Plus, T5 R-Design, T5 R-Design Special Edition, T6, T6 Inscription, T6 Momentum, T6 Platinum, T6 Premier Plus, T6 R-Design, T6 R-Design Platinum, T8 Inscription, T8 Polestar, T8 R-Design, T8 Recharge Core, T8 Recharge Inscription, T8 Recharge Plus, T8 Recharge Polestar, T8 Recharge R-Design, T8 Recharge R-Design Expression, T8 Recharge Ultimate | 4 Cyl 2.0 L GAS, 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
- S60 Cross Country | 2017-2018 | T5 | 4 Cyl 2.0 L GAS
- S80 | 2015-2016 | T5, T5 Platinum | 4 Cyl 2.0 L GAS
- S90 | 2017-2023 | B6 Inscription, B6 Momentum, B6 Plus, B6 R-Design, B6 Ultimate, T5 Inscription, T5 Momentum, T6 Inscription, T6 Momentum, T6 R-Design, T8 Inscription, T8 Momentum, T8 R-Design, T8 Recharge Inscription, T8 Recharge R-Design, T8 Recharge Ultimate | 4 Cyl 2.0 L GAS, 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV), 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
- V60 | 2015-2023 | Polestar, T5, T5 Dynamic, T5 Inscription, T5 Momentum, T5 Platinum, T5 Premier, T5 Premier Plus, T5 R-Design, T6 Inscription, T6 Momentum, T6 R-Design, T6 R-Design Platinum, T8 Polestar, T8 Recharge Polestar | 4 Cyl 2.0 L GAS, 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
- V60 Cross Country | 2020-2022, 2017-2018 | T5, T5 Platinum | 4 Cyl 2.0 L GAS
- V90 | 2018-2021 | T5 Inscription, T5 R-Design, T6 Inscription, T6 R-Design | 4 Cyl 2.0 L GAS
- V90 Cross Country | 2017-2021 | T5, T6, T6 Ocean Race | 4 Cyl 2.0 L GAS
- XC40 | 2019-2022 | T4 Inscription, T4 Momentum, T4 R-Design, T5 Inscription, T5 Momentum, T5 R-Design | 4 Cyl 2.0 L GAS
- XC60 | 2015-2023 | B5 Inscription, B5 Momentum, B5 R-Design, B6 Inscription, B6 R-Design, T5, T5 Dynamic, T5 Inscription, T5 Momentum, T5 Platinum, T5 Premier, T5 R-Design, T6, T6 Dynamic, T6 Inscription, T6 Momentum, T6 Ocean Race, T6 Platinum, T6 Premier, T6 R-Design, T8 Inscription, T8 Momentum, T8 Polestar, T8 R-Design, T8 Recharge Core, T8 Recharge Inscription, T8 Recharge Inscription Expression, T8 Recharge Plus, T8 Recharge Polestar, T8 Recharge R-Design, T8 Recharge Ultimate | 4 Cyl 2.0 L GAS, 4 Cyl 2.0 L MILD HYBRID EV-GAS (MHEV), 4 Cyl 2.0 L PLUG-IN HYBRID EV-GAS (PHEV)
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Volvo Temperature Sensor Part Number: 9445153
$37.42 MSRP: $43.82
You Save: $6.40 (15%)
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Product Specifications
- Other Name: IAT Sensor; Air Charge Temp; Coolant Temp Sensor; Temperature Sensor
Fits the following Volvo Models:
- S60 | 2001-2002 | 2.4T, AWD, Base, T5 | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- S70 | 1999-2000 | AWD, Base, GLT, GLT SE, T5 | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- S80 | 1999-2006 | 2.5T, 2.5T AWD, 2.9, T6, T6 Premier | 5 Cyl 2.5 L GAS, 6 Cyl 2.8 L GAS, 6 Cyl 2.9 L GAS
- V70 | 1999-2007 | 2.4, 2.4T, 2.5T, 2.5T AWD, AWD, Base, GLT, GLT SE, R AWD, T5, X/C, X/C AWD, X/C AWD SE | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS, 5 Cyl 2.5 L GAS
- XC70 | 2003-2007 | Base, Ocean Race, X/C | 5 Cyl 2.5 L GAS
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Volvo Temperature Sensor Part Number: 30865366
$42.48 MSRP: $49.74
You Save: $7.26 (15%)
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Product Specifications
- Other Name: Coolant Temperature Sensors; Temperature Sensor
Fits the following Volvo Models:
- S40 | 2000-2004 | Base, LSE | 4 Cyl 1.9 L GAS
- V40 | 2000-2004 | Base, LSE | 4 Cyl 1.9 L GAS
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Volvo Coolant Temperature Sensor Part Number: 30650752
$75.19 MSRP: $97.09
You Save: $21.90 (23%)
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Product Specifications
- Other Name: Engine Coolant Temperature Sensor; Coolant Temperature Sensor, Temperature Sensor
Fits the following Volvo Models:
- C30 | 2008-2013 | T5, T5 R-Design | 5 Cyl 2.5 L GAS
- C70 | 2006-2013 | T5 | 5 Cyl 2.5 L GAS
- S40 | 2004-2011 | 2.4i, i, T5, T5 R-Design | 5 Cyl 2.4 L GAS, 5 Cyl 2.5 L GAS
- S60 | 2012-2016 | T5, T5 Inscription Platinum, T5 Inscription Premier, T5 Platinum, T5 Premier, T5 Premier Plus | 5 Cyl 2.5 L GAS
- S60 Cross Country | 2016 | T5 Platinum | 5 Cyl 2.5 L GAS
- V50 | 2005-2011 | 2.4i, i, T5, T5 R-Design | 5 Cyl 2.4 L GAS, 5 Cyl 2.5 L GAS
- V60 | 2015-2016 | T5, T5 Platinum, T5 Premier, T5 Premier Plus | 5 Cyl 2.5 L GAS
- XC60 | 2015-2016 | T5, T5 Platinum, T5 Premier | 5 Cyl 2.5 L GAS
- XC70 | 2016 | T5, T5 Platinum, T5 Premier | 5 Cyl 2.5 L GAS
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Volvo Coolant Temperature Sensor Part Number: 9186486
$114.71 MSRP: $148.12
You Save: $33.41 (23%)
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Product Specifications
- Other Name: IAT Sensor; Coolant Temperature Sensor
Fits the following Volvo Models:
- 850 | 1993-1997 | Base, GLT, R, T-5, T-5R, Turbo | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- 960 | 1992-1997 | Base | 6 Cyl 2.9 L GAS
- C70 | 1998 | Base | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- S70 | 1998 | Base, GLT, T5 | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- S90 | 1998 | Base | 6 Cyl 2.9 L GAS
- V70 | 1998 | AWD, Base, GLT, T5, X/C AWD | 5 Cyl 2.3 L GAS, 5 Cyl 2.4 L GAS
- V90 | 1998 | Base | 6 Cyl 2.9 L GAS
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Volvo Temperature Sending Unit Part Number: 460191
$47.64 MSRP: $55.79
You Save: $8.15 (15%)
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Product Specifications
- Other Name: IAT Sensor; Coolant Temp Sensor; Temperature Sending Unit
Fits the following Volvo Models:
- 240 | 1991-1993 | Base, GL, SE | 4 Cyl 2.3 L GAS
- 244 | 1986-1988, 1984 | DL, GL | 4 Cyl 2.3 L GAS, 6 Cyl 2.4 L DIESEL
- 245 | 1984-1988 | Base, DL, GL | 4 Cyl 2.1 L GAS, 4 Cyl 2.3 L GAS, 6 Cyl 2.4 L DIESEL
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Volvo Temperature Sending Unit Part Number: 269085
$60.84 MSRP: $71.24
You Save: $10.40 (15%)
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Product Specifications
- Other Name: Temperature Sensor; Coolant Temperature Sensors; Temperature Sending Unit
Fits the following Volvo Models:
- 760 | 1984-1986 | GLE | 4 Cyl 2.3 L GAS, 6 Cyl 2.8 L GAS
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Volvo Temperature Sending Unit Part Number: 1362645
$53.39 MSRP: $62.51
You Save: $9.12 (15%)
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Product Specifications
- Other Name: Iat Sensor; Coolant Temperature Sensors; Temperature Sending Unit
Fits the following Volvo Models:
- 740 | 1987-1992 | Base, GLE, T | 4 Cyl 2.3 L GAS
- 760 | 1987-1988 | GLE | 4 Cyl 2.3 L GAS, 6 Cyl 2.8 L GAS
- 780 | 1991, 1987-1988 | Base | 4 Cyl 2.3 L GAS, 6 Cyl 2.8 L GAS
- 940 | 1991-1995 | Base, GL, GLE, SE, T | 4 Cyl 2.3 L GAS
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Volvo Temperature Sending Unit Part Number: 1367643
$194.26 MSRP: $231.25
You Save: $36.99 (16%)
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Product Specifications
- Other Name: Sensor; Coolant Temperature Sensors; Temperature Sending Unit
Fits the following Volvo Models:
- 760 | 1989-1990 | Base, GLE | 4 Cyl 2.3 L GAS, 6 Cyl 2.8 L GAS
- 780 | 1989-1990 | Base | 4 Cyl 2.3 L GAS, 6 Cyl 2.8 L GAS

Volvo Coolant Temperature Sensors Parts and Q&A

Temperature Sending Unit
1362645
Q: What is the function of Coolant Temperature Sensors and How to test, remove, and install it on Volvo 740?
A:
The Engine Coolant Temperature (ECT) sensor contains a resistance that changes with the engine coolant temperature, decreasing as the temperature increases and increasing as it decreases, giving a reference signal to the ECM that is related to the coolant temperature. This signal is used by the ECM to determine spark advance, E6R flow rate, air/fuel ratio and to determine engine temperature while also facilitating the operation of the temperature gauge by sending a signal to the instrument cluster. To test the sensor, set the key to the ON position with the engine OFF, measure the resistance across the terminals of the sensor and compare it to a reference chart to determine whether it is within specifications if not replace. For removal and installation, you first need to disconnect the negative battery cable - always take care to avoid any service to the radiator and cooling system when it is hot to avoid getting burns and risk of possible damage to pets from the ethylene glycol content - antifreeze. Drain the engine coolant and recycle, remove the parts that are blocking access to the sensor, disconnect the sensor, and unscrew it with the appropriate socket. To install, insert the new sensor in its mounting position and tighten it, reconnect the sensor, reconnect any parts that are removed, refill and bleed the cooling system, reconnect the negative battery cable, and finally check for any leaks.
Coolant Temperature Sensor
8653103
Q: How to replace coolant temperature sensors on Volvo V70?
A:
The coolant temperature sensor in the thermostat housing is used as an engine temperature source signal for the engine management system and the instrument panel temperature gauge. If a fault occurs in the sensor, or if there is a loss of signal because of poor electrical connections a fault code is logged in the engine management system ECU which can be accessed via the diagnostic connector in the centre console using a suitable fault code reader. In the event of a logged fault code, it is important to check the sensor wiring and connector carefully and while testing by substitution with a new unit is an option, further checks should be made using Volvo test equipment by a dealer or a suitably equipped specialist. To start removal, partially drain the cooling system down to just below the level of the sensor unit which is about 2.0 litres. For petrol models up to 2001, remove the two Torx bolts and lift off the thermostat housing cover and disconnect the wiring at the adjacent connector, and unscrew the sensor out of its position in the thermostat housing. For petrol models from 2002, remove the upper timing belt cover by undoing the clips or screws, disconnect the sensor wiring plug and then remove the sensor from the thermostat housing, removing the sensor seal if fitted and making sure to use a new one. For diesel models, pull the plastic cover on top of the engine straight up and disconnect the wiring plug before unscrewing the sensor from the housing, also discard the seal if fitted and replace it with a new one. When refitting, screw in the new sensor unit with a smear of sealant on the threads or new seal as applicable and reconnect the wiring connector and reassemble the thermostat housing making sure the screws are tightened securely. Finally, reconnect radiator hose or re-fit timing belt cover or engine cover as required and top up coolant level as required.