Today, almost every car is equipped with an air conditioning system. AC systems have become an active factor in driving safety, and can be considered as safety technology. Air conditioning system, like others, requires periodic maintenance and skillful diagnosis in case of malfunction. While design and operation of older systems is generally known, new solutions require more knowledge.
When there was a problem with system performance, or cooling system failed to operate at all, the first step was to check compressor drive, which was transferred by electromagnetic clutch. It was easy to check by means of ordinary multimeter capable of measuring coil resistance.
Newer air conditioning systems have compressor permanently connected to engine that operates as long as engine is running. In these systems air conditioning is controlled by special valve that increases or inhibits cooling intensity. How to check such compressor? Natural and safe solution is to use a dedicated device, ACT-2.
ACT-2 tester enables you to diagnose the following types of air conditioning compressors:
– electromagnetic clutch controlled compressor allows for electromagnetic clutch checkout,
– clutchless compressor – allows for checking of electromagnetic control valve.
The device can be used both on the test bench and directly in a car.
Tester specifications:
| Supply voltage | DC, ranged of 12 … 15V |
| Current draw | 70 mA (consumed by the tester itself without load) |
| Control signal generator | |
| Frequency range | 20Hz – 1000Hz |
| Frequency adjustment accuracy | 1Hz |
| Output amplitude | 0V up to supply voltage |
| Type of control | ground switching and power supply switching |
| Duty cycle range | 0% … 100% |
| Duty cycle accuracy | 0.1% |
| Number of outputs | 2 |
| Control signal measurement | |
| Frequency range | 20Hz … 1000Hz |
| Input signal amplitude | 0V up to supply voltage |
| Threshold level | 2.5V |
| Protection | |
| Over-voltage | supply over 18V |
| Over-current | built-in output short circuit protection and fuse (6.3A) |
