Engine Controls - System/component Tests: Other Volvo V90 I

Checking Air Intake System For Leakage

1. Check that all hoses are undamaged and in place with hose clamps tightened.
2. Disconnect fresh air hose from MAF sensor. Install Volvo adapter (999 5545) with pressure regulator (999 5544) on fresh air hose and tighten hose clamp. (Scheme 21)
3. Clamp crankcase ventilation hose with hose clamp. Remove oil filler cap. Remove lower hose from canister purge valve.
4. Connect compressed air hose and adjust regulator to obtain a maximum pressure of 4.35 psi (0.3 bar).
5. Check components (A-V). (Scheme 22) Check connectors (A-G). (Scheme 23) If leak is suspected, spray soap solution onto area of suspected leak to find where air is escaping from. Repair as necessary.

Scheme 21

Scheme 22

Scheme 23

Checking EVAP Canister Purge Valve

1. Remove valve from bracket and soundproofing from valve to gain access to EVAP valve. If attached, remove Volvo adapter (999 5545) and pressure regulator (999 5544) from fresh air hose. Remove EVAP valve hoses and connector.
2. Connect vacuum pump (999 5843) hose to connection under connector. (Scheme 24) Pump up vacuum. Vacuum gauge should indicate steady vacuum. If vacuum drops, replace EVAP valve.
3. After repairs, reinstall valve, hoses soundproofing and connector. Use pliers (981 4215) to install NEW hose clamp.

Scheme 24

Preliminary Checks

1. Warm engine to normal operating temperature. Turn off engine. If turbine shaft does not stop rotating shortly after engine stops, remove intake hose from compressor housing.
2. Verify compressor wheel rotates freely. Ensure compressor wheel does not scrape against compressor housing when wheel is pushed radially or axially.

Turbocharger Control Valve Control

1. Start engine. Using scan tool, go into scrolling values. Accelerate hard several times and watch parameter TC CONTROL. If parameter constantly exceeds 90 percent, go to next step. If parameter does not constantly exceed 90 percent, check ECM power and ground circuits. See «ELECTRONIC CONTROL MODULE (ECM)»(ref-15338-S38571622542000122900000) .
2. Turn ignition off. Check hose between turbocharger control valve and fresh air intake for blockage or damage. Check nipples on turbocharger control valve and fresh air intake for blockage. Repair as necessary.

Checking Exhaust System

1. Remove exhaust system tail pipe. Attach Volvo adapter (999 5546) and pressure regulator (999 5544) to exhaust system. (Scheme 25) Adjust pressure to 5.8 psi (0.4 bar). Lower pressure may be necessary, depending on condition of exhaust system.
2. Check exhaust system by spraying soapy water on all joints and connections between cylinder head and rear HO2S. Only extremely small and slowly increasing bubbles are permissible. Repair as necessary.

Scheme 25

COMPUTERIZED ENGINE CONTROLS

ELECTRONIC CONTROL MODULE (ECM)

Note. When measuring resistance and voltage at ECM, use Breakout Box (981-3190 ) and Adapter (981-3195). DO NOT measure resistance and voltage at ECM connector.

Preliminary Check

Turn ignition off. Disconnect PCM connector. PCM is located at right front of engine compartment. Visually inspect all terminal connector sleeves to ensure no terminals are damaged.

Power Circuit Check

Ensure ignition is off. Install breakout box and adapter. (Scheme 26) Connect adapter connector "A" to breakout box. Measure voltage between breakout box terminal No. 13 (ground) and terminals No. 12, 26 and 27. Battery voltage should be present at all terminals. If voltage is not as specified, check No. 1 fuse, wiring and main relay. Repair as necessary.

Ground Circuit Checks

Turn ignition off. Install breakout box and adapter. Connect adapter connector "A" to breakout box. Measure resistance between ground and breakout box terminals No. 13, 28 and 42. Ohmmeter should indicate about zero ohms at all terminals.

Scheme 26

ENGINE SENSORS & SWITCHES

CAMSHAFT POSITION SENSOR

If circuit or component is faulty, a trouble code should set. See TESTS W/CODES article.

CRANKSHAFT POSITION SENSOR

If circuit or component is faulty, a trouble code should set. See TESTS W/CODES article.

ENGINE COOLANT TEMPERATURE SENSOR

Disconnect Engine Coolant Temperature (ECT) sensor connector. Using an ohmmeter, measure resistance between ECT sensor terminals. See ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE table. If resistance is not as specified, replace sensor.

ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE

MASS AIRFLOW (MAF) SENSOR

Turn ignition on. Locate MAF sensor connector. DO NOT disconnect connector. Backprobing connector, measure voltage between connector terminals No. 2 and 4. (Scheme 27) If voltage is not 0.1-0.2 volt, replace MAF sensor.

Scheme 27

HEATED OXYGEN SENSOR

1. Turn ignition off. Disconnect ECM connector. Connect Breakout Box (981-3190 ) and Adapter (951-1351 ).
2. To check oxygen sensor signal, connect ohmmeter between breakout box terminal No. 27 and terminal No. 14 (front sensor) or No. 29 (rear sensor). Ohmmeter should read 1.5-13 ohms.

ACCELEROMETER

If circuit or component is faulty, a trouble code should set. See TESTS W/CODES article.

THROTTLE POSITION (TP) SENSOR

Start and idle engine. Using scan tool, enter scrolling values list. Read off throttle angle. Throttle angle should be zero degrees when engine is idling and should increase as accelerator pedal is depressed.

FUEL PUMP RELAY

1. Remove fuel pump relay from fuse/relay box. On C70, S70 and V70, fuel pump relay is located in electrical distribution box in engine compartment. On S90 and V90, fuel pump relay is located in electrical distribution box on left side of instrument panel. Connect jumper wire between fuel pump relay terminals No. 1 and 3. (Scheme 28) Turn ignition on. If fuel pump does not start, go to next step. If fuel pump starts, replace fuel pump relay.
2. Turn ignition off. To check relay ground, connect ohmmeter between ground and fuel pump relay terminal No. 2. (Scheme 28) Ohmmeter should indicate about zero ohms. If ohmmeter does not indicate about zero ohms, check wiring between fuel pump relay and ground.
3. To check fuel pump relay voltage supply, connect voltmeter between ground and fuel pump relay terminal No. 1. (Scheme 28) Turn ignition on. Battery voltage should be present. If battery voltage is not present, check wiring between fuel pump relay and fuse No. 2.
4. Turn ignition off. Connect ohmmeter between ground and relay terminal No. 3. (Scheme 28) About 1.5 ohms should be present. If about 1.5 ohms are not present, check resistance at fuel pump connector to determine whether fault is in pump or wiring.
5. To check fuel injection control signal to fuel pump relay, connect voltmeter between ground and fuel pump relay terminal No. 4. (Scheme 28) Operate starter motor. If voltmeter indicates about 3 volts, replace relay. If voltage is not to specification, check wiring between fuel pump relay and ECM.

Scheme 28

FUEL SYSTEM

Note. For fuel system pressure testing, see BASIC TESTING article.

Fuel Pressure Regulator

1. Install Connector (998-9725) to Fuel Pressure Gauge (999-5011). Using Adapter (999-5479), connect pressure gauge to valve on fuel distribution manifold. Turn valve in direction of adapter. Connect other gauge connection to Fuel Drainage Unit (981-2270, 2273 and 2282).
2. Remove fuel pump relay from electrical distribution box. On C70, S70 and V70, fuel pump relay is located in electrical distribution box in engine compartment. On S90 and V90, fuel pump relay is located in electrical distribution box on left side of instrument panel. Connect jumper wire between fuel pump relay terminals No. 1 and 3. Turn ignition on. Fuel pump should start. If system pressure is 43.5 psi (300 kPa), go to step 5) .
3. If system pressure is too high, remove jumper wire. Disconnect pressure regulator return and vacuum lines and blow through lines. If both lines are okay, replace regulator and recheck pressure.
4. If system pressure is too low, squeeze return line and ensure pressure rises. Do not allow pressure to exceed 87 psi (600 kPa). If pressure rises quickly, pump and line are okay. Replace pressure regulator and recheck system pressure. If pressure rises slowly, check for blocked fuel filter, fuel pump strainer or fuel lines. If pressure does not rise, replace pump.
5. If system pressure was 43.5 psi (300 kPa) in step 2), check operation of pressure regulator by connecting Vacuum Pump (999-5843) to pressure regulator. Apply vacuum to regulator. Ensure system pressure falls by same amount as regulator pressure.
6. Turn ignition off. Remove jumper wire between fuel pump relay terminals No. 1 and 3. Reinstall fuel pump relay. Check fuel system residual pressure. Pressure should not fall below 20 psi (200 kPa) in less than 20 minutes. If fuel pressure falls faster, check injectors, pressure regulator, and fuel pump. Disconnect Pressure Gauge (999-5011).

Fuel Injectors

Turn ignition off. Disconnect fuel injector connector. With injector temperature at about 68°F (20°C), measure resistance between injector terminals. See FUEL INJECTOR table. Replace injector as necessary.

FUEL INJECTOR RESISTANCE

IGNITION SYSTEM

Note. For basic ignition checks, see BASIC TESTING article.

Knock Sensors

If circuit or component is faulty, a DTC should set. See TESTS W/CODES article.

FUEL EVAPORATIVE (EVAP)

If circuit or component is faulty, a DTC should set. See TESTS W/CODES article.