Signal Specification Additional Heater 912-D/B
WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.
General
All values given below are between the respective terminal in column 1 and terminal #3 (power ground) unless otherwise stated in brackets after the table entry. Control module terminals #1-#16 correspond to #1-#16 on the breakout box.
NOTE:
It is important to connect the breakout box and check ground terminals before taking readings.
| U= | DC voltage in volts (V) | UAC = | AC voltage in volts (V) |
| Ubat = | Battery voltage (V) | f= | Frequency in Hertz (Hz) |
| Ulow = | Voltage approximately 0 V | % duty= | Duty cycle (pulse ratio) as a percentage (%) |
| t= | Time in milliseconds (ms) | - | - |
| Terminal | Signal Type | Ignition On | Engine Idling | Remarks |
| #1 | Glow plug signal | Glow plug off: U=Ulow Glow plug on: Pulse ratio (% duty) 0% |
Pulse ratio (% duty) increases with glow plug intensity. | |
| #2 | Control signal passenger compartment blower fan (when installed as accessory) | No accessory installation: U≈0 V Relay installed Relay not activated: U≈12 V Relay activated: U less than 2.5 V |
- | |
| #3 | Power ground Measured to battery negative terminal (-) |
Ulow | - | |
| #4 | Signal ground, outside temperature sensor, Coolant temperature sensor and flame sensor | Ulow | - | |
| #5 | Signal from generator (GEN) | U < 2.75 V | U > 7 V | - |
| #6 | Diagnostic lead, K-link | U≈8.1 V | U≈9.8 V | If the fault tracing-instrument is connected the other values apply |
| #7 | Outside temperature sensor signal | +20°C: U≈0.5 V | Voltage increases with decreasing temperature | |
| #8 | Flame sensor signal | Flame not lit: U≈5 V Flame lit: U<1.5 V |
- | |
| #9 | 30-supply (Power supply from battery) | Ubat | - | |
| #10 | Combustion fan control signal | Combustion fan off and power supply off: Ulow Combustion fan off and power supply on: Ubat Fan on: Pulse ratio (% duty) 0% |
The pulse ratio (% duty) increases with fan speed. | |
| #11 | Combustion fan, fuel pump and water pump power supply | Power supply off: Ulow Power supply on: Ubat |
- | |
| #12 | Water pump control signal | Water pump off and power supply off: Ulow Water pump off and power supply on: Ubat Water pump on and power supply on: Ulow |
- | |
| #13 | Fuel pump control signal | Fuel pump off: f=0 Hz Fuel pump on: f>0 Hz |
Frequency increases with pump speed | |
| #14 | Timer control signal | Timer active: U > 7 V Heater start after rest: U < 2.75 V Remarks: 2.75 V < U < 7 V |
- | |
| #15 | 15-supply (power supply from ignition switch) | Ubat | Ubat | - |
| #16 | Coolant temperature sensor signal | +20°C: U≈3.5 V | Voltage decreases with increasing temperature | |