A/C High Side Test

A/C High Side BD 27 Test is made with engine running at 2000 RPM.

NOTE: Run High Side Test only if Code B449 is set. If pressures and temperatures are both high, check for sources of excess head pressure.

If BD 27 exceeds 199°F (93°C) but pressure remains below 380 psi, sensor is out of specification.

NOTE: Compressor will disengage and Code B449 will set if temperature sensor value exceeds 199°F.

Fig 1: Chart 10, A/C System Performance Test