1998 Volvo C70 2D Convertible, AutomaticFACTORY OEM SERVICE PROCEDURE

Activating components/functions

Activate the Volvo Scan Tool (ST) Components/functions  by pressing the YES/NO button to start and stop activation.

Turn Ignition Key to position II, engine not running.

No.  Component  Function 
1 AIR PUMP Pulsed secondary air injection system (PAIR) pump
Pulsed secondary air injection system (PAIR) pump is on for 3 seconds, off for 3 seconds, on for 3 seconds for a total of 30 seconds. The pulsed secondary air injection system (PAIR) pump can be heard clearly.
2 SAS VALVE Pulsed secondary air injection system (PAIR) solenoid valve
The solenoid valve is open for 0.5 second, closed for 0.5 second, open for 0.5 second for a total of 30 seconds.
3 FUEL PUMP Fuel pump (FP)
The engine control module (ECM) controls the fuel pump (FP) relay with a 42 Hz signal for 30 seconds.
In turn the relay controls the fuel pump (FP). It is hard to hear if the pump is operating, but by listening carefully one can hear the pump start/stop.
4 EVAP-VALVE Canister purge (CP) valve
The canister purge (CP) valve is open for 1 second, closed for 1 second, open for 1 second for a total of 30 seconds. The canister purge (CP) valve clicks.
5 CANISTER VALVE* EVAP canister shut-off valve
The EVAP canister shut-off valve is open for 1 second, closed for 1 second, open for 1 second for a total of 30 seconds. The EVAP canister shut-off valve clicks.
6 HEAT HO2S 1 Front heated oxygen sensor (HO2S) preheating
Preheating is on for 12 ms, off for 0.5 seconds, on for 12 ms for a total of 30 seconds. Use a voltmeter to check the signal, t=12 ms/ f=1.9 Hz.
7 HEAT HO2S 2 Rear heated oxygen sensor (HO2S) preheating
Preheating is on for 12 ms, off for 0.5 seconds, on for 12 ms for a total of 30 seconds. Use a voltmeter to check the signal, t=12 ms/ f=1.9 Hz.
8 ENG FAN LOW-SPD Engine cooling fan (FC) low-speed
Engine cooling fan (FC) runs at low-speed is for 3 seconds, off for 3 seconds, runs at low-speed for 3 seconds for a total of 30 seconds. The engine cooling fan (FC) can be heard clearly.
9 ENG FAN HI-SPD Engine cooling fan (FC) high-speed
Engine cooling fan (FC) runs at low-speed is for 3 seconds, off for 3 seconds, runs at low-speed for 3 seconds for a total of 30 seconds. The engine cooling fan (FC) can be heard clearly.
10 INJECTOR. 1 Injector 1
The injector is open for 12 ms, closed for 1 second, open for 12 ms etc for a total of 10 seconds. The injector clicks.
11 INJECTOR. 2 Injector 2
The injector is open for 12 ms, closed for 1 second, open for 12 ms etc for a total of 10 seconds. The injector clicks.
12 INJECTOR. 3 Injector 3
The injector is open for 12 ms, closed for 1 second, open for 12 ms etc for a total of 10 seconds. The injector clicks.
13 INJECTOR. 4 Injector 4
The injector is open for 12 ms, closed for 1 second, open for 12 ms etc for a total of 10 seconds. The injector clicks.
14 INJECTOR. 5 Injector 5
The injector is open for 12 ms, closed for 1 second, open for 12 ms etc for a total of 10 seconds. The injector clicks.
15 IAC VALVE Idle air control (IAC) valve
Opening coil activated for 0.25 second, closing coil activated for 0.25 second, opening coil activated for 0.25 second for a total of 30 seconds. The idle air control (IAC) valve clicks.
16 Air conditioning (A/C) relay Air conditioning (A/C) relay
The relay is operated for 1 second, released for 1 second, operated for 1 second etc. The air conditioning (A/C) relay and compressor click. The air conditioning (A/C) system must be on and the blower fan switch on low-speed.
17 RPM Engine speed (RPM) signal to combined instrument panel.
The engine control module (ECM) transmits a signal to the combined instrument panel corresponding to approximately 1250 rpm (the signal is high for 12 ms and low for 12 ms) for a total of 30 seconds. The tachometer in the combined instrument reads approximately 1250 rpm.
18 ECT Engine coolant temperature (ECT) signal to the combined instrument panel
The engine control module (ECM) transmits a signal to the combined instrument panel corresponding to approximately 102°C (the signal is high for 24 ms and low for 24 ms) for a total of 30 seconds. Because of the slowness of the temperature gauge, it will not reach this temperature before the function is interrupted.
19 MIL Malfunction indicator lamp (MIL) in combined instrument panel
The lamp is lit for 1 second, out for 1 second, lit for 1 second for a total of 30 seconds. The malfunction indicator lamp (MIL) is flashing
20 LOAD TQ Load signal to automatic transmission.
The engine control module (ECM) transmits a signal to the transmission control module (TCM) which is low for 12 ms and high for 12 ms for a total of 30 seconds. Use a voltmeter to check the signal, t=12 ms/ f=41Hz.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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