2020 VOLVO S90 engine

MAINTENANCE AND SERVICE
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Start battery
The vehicle has a single-pole electrical sys- tem that uses the chassis and engine mountas conductors. The start battery is used to start the electrical system and power the starter motor andother electrical equipment in the vehicle. The start battery should only be replaced by a workshop 22
.
The vehicle has a voltage-regulated alternating current generator. The start battery is a 12 V battery, dimen- sioned for the carbon dioxide-reducing func-tions Start/Stop and regenerative chargingand to support the function of the vehicle'svarious systems. The service life and performance of the start battery are affected by factors such as drivingstyle, driving conditions, climate, battery dis-charges, number of starts, etc. Never disconnect the start battery while the engine is running.
Make sure the cables to the start batteryare correctly connected and the clampsare securely tightened.
WARNING
Batteries generate hydrogen gas, which is flammable and explosive.
Do not connect the jumper cable toany part of the fuel system or to anymoving parts. Avoid touching hotmanifolds.
Battery fluid contains sulfuric acid. Donot allow battery fluid to contact eyes,skin, fabrics or painted surfaces.
If contact occurs, flush the affectedarea immediately with water. Obtainmedical help immediately if eyes areaffected.
Never expose the battery to open flameor electric spark. Do not smoke nearthe battery. Failure to follow theinstructions for jump starting can leadto injury.
Connection points
WARNING
California Proposition 65 Operating, servicing and maintaining a pas- senger vehicle can expose you to chemi-cals including engine exhaust, carbon mon-oxide, phthalates, and lead, which areknown to the State of California to causecancer and birth defects or other reproduc-tive harm. To minimize exposure, avoidbreathing exhaust, do not idle the engineexcept as necessary, service your vehicle ina well ventilated area and wear gloves orwash your hands frequently when servicingyour vehicle. For more information go towww.P65Warnings.ca.gov/passenger-vehicle.
Use the vehicle's connection points in the engine compartment to connect an externalstart battery or battery charger. The battery terminals on the car's start battery in the luggage/cargo area must not be used.
If the start battery is being charged, the sup-port battery will also be charged.
21 LED (Light Emitting Diode)
22 An authorized Volvo workshop is recommended.

MAINTENANCE AND SERVICE
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Support battery Vehicles with the Start/Stop function are equipped with two batteries – a more power-ful 12 V start battery and a support batterythat provides stronger current during thefunction's start sequence.
The 12 V support battery is located in a box next to the spring strut in the engine compartment.
NOTE
The higher the current consumption in the vehicle, the more the alternator hasto work and the batteries have to becharged = increased fuel consumption.
When the starter battery capacity hasdropped below the lowest permissiblelevel, the Start/Stop function is disen-gaged.
When the Start/Stop function is temporarily reduced due to high current consumption: The engine will auto-start, even if the driver does not lift their foot from thebrake pedal.
The support battery does not normally requiremore service than the start battery. If you haveany questions or concerns, consult a work-shop ‒ an authorized Volvo workshop is rec-
ommended.
CAUTION
If the following is not observed, the Start/ Stop function may temporarily stop work-ing after connection of an external starterbattery or battery charger:
The negative battery terminal of thevehicle's starter battery must
never be
used to connect an external starterbattery or battery charger – only thevehicle's negative charging pointshould be used as a grounding point.
NOTE
If the starter battery has been discharged to the extent that the vehicle does not havenormal electrical functions and the enginemust then be jump-started with an externalbattery or a battery charger, the Start/Stopfunction may remain activated. If the Start/Stop function shortly thereafter auto-stopsthe engine, there is a huge risk that auto-start of the engine will fail due to insuffi-cient battery capacity since the battery hadnot had time to recharge. If the vehicle has been jump-started or if there has not been enough time for thebattery to be charged with a batterycharger, the Start/Stop function should betemporarily deactivated until the batteryhas been recharged by the vehicle. At anambient temperature of about +15°C(about 60°F), the battery must be chargedby the vehicle for at least one hour. Atlower ambient temperatures, the chargingtime can increase to 3-4 hours. It is advisa-ble to charge the battery with an externalbattery charger.
Specifications for support battery
Type AGM
Voltage (V) 12

MAINTENANCE AND SERVICE
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Battery recycling Start batteries and support batteries contain lead and must be recycled in an environmen-tally sound manner at the end of their servicelife.
Consult a workshop if you are uncertain of how to dispose of this type of waste ‒ an
authorized Volvo workshop is recommended.
Related information
Start battery (p. 567)
Support battery (p. 571)
Battery symbols (p. 572)
Fuses and fuseboxes All electrical functions and components are protected by a number of fuses in order toprotect the vehicle's electrical system fromdamage by short circuiting or overloading.
WARNING
Never use a foreign object or a fuse with a higher amperage than that specified toreplace a fuse. This could cause significantdamage to the electrical system and possi-bly lead to a fire.
If any electrical component or function is not responding, the component may have blown afuse due to temporary overload. If the samefuse blows repeatedly, there may be a prob-lem with the component. Volvo recommendscontacting an authorized Volvo workshop tohave the component checked.
Location of fuseboxes
The illustration is generic - appearance may vary according to vehicle model.
Engine compartment
Under the glove compartment
Trunk/cargo compartment
Related information
Replacing fuses (p. 574)
Fuses in the trunk (p. 586)
Fuses in the engine compartment (p. 575)
Fuses under the glove compartment(p. 580)

MAINTENANCE AND SERVICE
574
Replacing fuses
All electrical functions and components are protected by a number of fuses in order toprotect the vehicle's electrical system fromdamage by short circuiting or overloading.
1. Refer to the fuse diagram to locate the fuse.
2. Pull out the fuse and examine it from the side to determine if the curved metal wire in the fuse is intact.
3. If the wire is broken, replace the fuse with a new fuse of the same color and amper-age.
WARNING
Never use a foreign object or a fuse with a higher amperage than that specified toreplace a fuse. This could cause significantdamage to the electrical system and possi-bly lead to a fire.
WARNING
Contact an authorized Volvo workshop for assistance replacing fuses not listed in theOwner's Manual. If fuse replacement isperformed incorrectly, significant damagecan be caused to the electrical system.
Related information
Fuses and fuseboxes (p. 573)
Fuses in the trunk (p. 586)
Fuses in the engine compartment (p. 575)
Fuses under the glove compartment(p. 580)

MAINTENANCE AND SERVICE
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Fuses in the engine compartment The fuses in the engine compartment help protect electrical components such as engineand brake functions.

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MAINTENANCE AND SERVICE
576Fuse pliers are provided on the inside of the fuse box cover to assist in removing andinserting fuses.
There are also spaces for several extra fuses inthe fusebox.
PositionsThere is a decal with a diagram of the loca-tions of the fuses on the inside of the cover.
Function
Ampere Type
– – Micro
–– Micro
–– Micro
Ignition coils (gasoline); Spark plug (gasoline); Exhaust sensor; Diesel particulate sensor15 Micro
Oil pump solenoid; A/C magnetic coupling; heated oxygen sensor, center (gasoline); heated oxygen sensor, rear (diesel); heated oxygen sensor, front (gasoline/diesel)15 Micro
Vacuum regulator; Valve; Output pulse valve (diesel); Oil level/temperature sensor (diesel); Glow plug (GCU) (diesel) 7.5 Micro
Engine control module; actuator; throttle unit; EGR valve (diesel); turbo position sensor (diesel); turbocharger valve (gasoline)20 Micro
Engine control module
5 Micro
–– Micro
Solenoids (gasoline); Valve; Engine cooling system thermostat (gasoline); EGR cooling pump (diesel); Glow control module (diesel); Supercharger clutch (gasoline); Crankshaft ventilation heater (diesel); Transmission oil cooler valve (die-sel)10 Micro
Spoiler damper control module; Cooler damper control module; Relay coils for output pulse (diesel) 5 Micro
Coolant pump
15 Micro

MAINTENANCE AND SERVICE
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* Option/accessory.577
Function Ampere Type
Engine control module 20 Micro
Starter motor40
MCaseA
Starter motor
Shunt
MCaseA
Fuel filter heater (diesel)
30
MCaseA
–
–
MCaseA
Calculation module
5 Micro
–– Micro
–– Micro
–– Micro
–– Micro
Front USB port in tunnel console, rear* 5 Micro
12 V outlet in tunnel console, front
15 Micro
12 V socket in tunnel console between the second row of seats*
230 V socket in tunnel console between the second row of seats *15 Micro
12 V outlet in trunk/cargo compartment
* 15 Micro
–
– Micro
Driver-side headlight, LEDB
15 Micro

MAINTENANCE AND SERVICE
579
FunctionAmpere Type
– –
MCaseA
Fed when ignition is on: engine control module, transmission components, electrical power steering, central electrical module, brake system control module 5 Micro
–
– Micro
Passenger-side headlight, LEDB
15 Micro
– – Micro
–– Micro
Battery connection control module 5 Micro
Airbags; Passenger weight sensor5 Micro
Driver-side headlight, LEDB
15 Micro
Accelerator pedal sensor 5 Micro
A
This type of fuse should be replaced by a workshop. An authorized Volvo workshop is recommended.
B LED (Light Emitting Diode)
Related information
Fuses and fuseboxes (p. 573)
Replacing fuses (p. 574)