System Troubleshooting

A/C REFRIGERANT SYSTEM (R-134A), TROUBLESHOOTING

Test requirements

Using VAG 1551 Scan Tool (ST), check Diagnostic Trouble Code (DTC) memory for any electrical, vacuum or air distribution malfunctions, On Board Diagnostic (OBD) - Air conditioning; correct/repair as necessary before proceeding.

- If one of the following conditions exists, follow recommended service:

A/C does not cool (cooling has stopped completely)

- check A/C system pressures, see page 87-54

Insufficient cooling during all driving speeds or Engine Speeds (RPM)

- check A/C system pressures

A/C compressor noisy

- tighten A/C compressor and compressor bracket mounting bolts using torque wrench

- check routing of A/C refrigerant hoses and lines; hoses and lines must not contact other components and must be installed without binding, reposition or realign as necessary

A/C compressor noisy immediately after switching A/C ON and/or when driving around corners or braking (refrigerant shock) - system is overcharged

- discharge A/C refrigerant system, evacuate and recharge

With an otherwise properly operating A/C system, water sprays out of instrument panel vents

- check evaporator water drain hose for proper routing (should not be kinked)

- check evaporator water drain valve

^ must not be plugged with wax, dirt or undercoating (clean if necessary)

^ valve flap must close properly

- check plenum tray

^ must be properly installed and not damaged