What is the 15 amp fuse for connected to the battery of my Volvo v70 1999 turbo

Did you connect the Batteries you jumped with correctly? In Parallel you have 12 volts (correct) in Series you have 24 volts (incorrect). Check your main power fuse ( Big 60 amp or 40Amp) located in plastic box close to the battery on the inner fender well. Be careful jumping dead batteries! Explosion hazard exist, wear eye protection always.

FUSE PANEL LOCATION
The fuse panel is located in the engine compartment. A label on the inside of the cover lists the fuse amperage and circuits protected.
volvo 850 fuses fuse panel layout service repair manual
FUSE PANEL IDENTIFICATION
Fig. 1: Fuse Panel Identification
Courtesy of Volvo Cars of North America.
WARNING: Always disconnect battery ground cable before servicing "high-current fuses. It is recommended that "high-current" fuses be replaced by a qualified technician.
* 1 - 15 Amp
Fuel Injection, Distributor Ignition, Automatic Gearbox
* 2 - 15 Amp
Fuel Pump, Alarm System
* 3 - 10 Amp
Courtesy Lights, Oil Level Sensor
* 4 - Not Used (1993-95)
* 4 - 10 Amp (1996)
Electronic Start Inhibitor (Immobilizer)
* 5 - 30 Amp
ECC Blower (Speed 4)
* 6 - 25 Amp
Central Locking System, Alarm
* 7 - 15 Amp
Audio System (Amplifier)
* 8 - 25 Amp (1993-95)
Power Antenna, Trailer Connector
* 8 - 40 Amp (1996)
Electronic Start Inhibitor (Immobilizer)
* 9 - 30 Amp
ABS, Traction Control System
* 10 - Not Used (1993-95)
* 10 - 15 Amp (1996)
Heated Rear Seat (If Equipped)
* 11 - 30 Amp
Heated Rear Window & Side Mirrors
* 12 - 10 Amp
Brake Lights
* 13 - 15 Amp
Hazard Flashers, Headlight Flashers, Alarm
* 14 - 30 Amp
ABS, Traction Control System
* 15 - 10 Amp (1993-95)
Audio System, Courtesy Lights, Door Open Light, Trunk Light, Glove Box Light, Remote Control Central Locking System,
Oil Level Sensor, Seat Belt Reminder
* 15 - 10 Amp (1996)
Audio System, Courtesy Lights, Door Open Light, Trunk Light, Glove Box Light, Remote Control Central Locking System,
Oil Level Sensor, Seat Belt Reminder, Data Link Connector
* 16 - 30 Amp (1993-95) Accessories
* 16 - 30 Amp (1996)
Power Antenna, Trailer Connector, Accessories
* 17 - 10 Amp
Key Reminder
* 18 - 25 Amp (1993-95)
Heated Front Seats, Power Mirrors
* 18 - 15 Amp (1996) Front Fog Lamps
* 19 - 15 Amp
Left High Beam Headlight
* 20 - 15 Amp
Right High Beam Headlight, High Beam Indicator
* 21 - 15 Amp
Left Low Beam Headlight
* 22 - 15 Amp
Right Low Beam Headlight
* 23 - 10 Amp
Left Parking Light, License Light
* 24 - 10 Amp
Right Parking Light, Bulb Failure Warning Sensor
* 25 - 10 Amp
Rear Fog Lamps, Fog Lamp Indicator
* 26 - Not Used (1993-95)
* 26 - 25 Amp (1996)
Heated Front Seats, Power Mirrors
* 27 - 15 Amp
Back-Up Lights, Turn Signals
* 28 - 10 Amp
Cruise Control, Heated Rear Window, Seat Belt Reminder Light, Shiftlock, Bulb Failure Warning Sensor, Heated Rear Seat
* 29 - 15 Amp
ABS, Traction Control System
* 30 - 10 Amp
Cigarette Lighter
* 31 - 25 Amp
ECC, ECC Blower (Speeds 1-3)
* 32 - 10 Amp
Audio System, Remote Controlled Central Locking System
* 33 - 15 Amp (1993-95)
Power Seats, OBD Test Socket, Tailgate Washer/Wipe (Wagon)
* 33 - 15 Amp (1996)
Power Seats, Tailgate Washer/Wipe (Wagon)
* 34 - 25 Amp
Windshield Wiper/Washer, Horn, Headlight Washer/Wiper
* 35 - 10 Amp
Instrument Lights, Sun Roof, Traction Control System
* 36 - Not Used
* 37 - Circuit Breaker
Power Windows, Power Sun Roof
* 38 - Not Used
* 39 - Circuit Breaker
Drivers Power Seat
* 40 - Circuit Breaker
Passengers Power Seat
RELAY PANEL LOCATION
The relay panel is located at the left corner of the instrument panel.
i copied this off a volvo site Hope this helps

Fusible links are either by the battery or down by the starter. But if everything else is working, this is not the problem You have a bad connection(pull the fuse and reinsert it or a broken wire). Most wires break close the the plugs.

It looks easy for the 940 but I am not sure about the 940 turbo, as maybe some of the turbo parts are in the way. I'm not sure about that, since there is no documentation on the turbo model vs. the 940 standard model. If you can follow the following instructions, then I would give it a whirl.

REMOVAL & INSTALLATION - 1993 Volvo 940

1. Disconnect the negative battery cable at the battery.
2. Disconnect the leads from the starter motor.
3. Remove the starter motor retaining bolts.
4. Remove the starter motor from the vehicle. To install:
   
5. Position the starter motor to the flywheel housing.
6. Apply locking compound to the bolt threads and install the retaining bolts finger-tight.
7. Tighten the bolts to approximately 25 ft. lbs. (34 Nm).
8. Connect the starter motor leads and the negative battery cable. Fig. 1: Unfasten the nut retaining the starter cables . . .
   Fig. 2: . . . and remove the starter cables
   Fig. 3: Unfasten the starter retaining bolts . . .
   Fig. 4: . . . and remove the starter from the engine
   

You can check 2 things. 1., have someone in the car to turn the key to the start position. Tap the starter with a small hammer and see if it cranks. If it does, replace the starter. 2., have the battery tested as well as the connections to the battery. Corrosion builds and can cause heavy resistance to heavy loads(like starting). These are the 2 most likely causes. Let me know if you need further assistance.

Remove the Intake tube clamps unbolt the exhaust bolts and unhook the turbo waste gate it it has the toy stock turbo then lift up. getting to it is the hard part. You can also buy a turbo kit or a new turbo for &50 bucks that would boost your fuel econemy by 15% and power about the same or a little more. This also depends if it has the Volvo turbo on it the flange is bolted onto the surface of the turbo or if it has a different setup non factory.

Go to this web sight and it's all there. http://www.volvoclub.org.uk/faq/ElectricalCircuitsRelays.html#RelayLocations

check the large relay in the fuse box and push it down it works a number things