Power Steering and AC not Working: What Could Be the Reason

When the power steering and air conditioning systems in your vehicle suddenly shows difficulties in functioning, it can present a real problem. 

Lack of either of these systems can make driving much more difficult and uncomfortable. 

Methodically tracing the root cause takes patience, but it is vital to get your vehicle back on the road.

Figuring Out the Issues

Drive Belt Issues

• Start diagnosis by verifying the drive belt that runs these components. 

• A broken or loose belt is unable to turn the pump pulleys. 

• Inspect along the entire length for cracks or fraying and replace if damaged. 

• Check automatic tensioners for leaks and smooth operation. 

• Adjust the belt tension to the specifications if it is loose.

Voltage Issues

• Next, trace the high-voltage electrical supply that feeds to both of the systems. 

• Power steering and A/C rely on 350-450 volts in three phases with the alternating current to drive the electric motors and compressors. 

• Examine fuses, wiring, and connections for damage. 

• Many vehicles have three large fuses that supply this power, and also check for blown fuses as the next step.

Battery Issues

• Determine if the failures correspond to any other parts that may cut out, like headlights or radiator fans. 

• This may point to a low-voltage battery that enables to supply the sufficient current during peak loads. 

• Have the battery tested under load for performance issues or sulfated cells. 

• Charge the battery to the maximum level or replace the battery as necessary.

Scanning for Codes

• Scan the vehicle computer OBD codes that could indicate any sensor or computer faults that may affects the operations. 

• The power steering control module monitors multiple parameters like vehicle speed, steering angle, and torque sensors. 

• Similarly, the AC relies on pressure transducers and temperature sensors for activation. 

• Codes for these sensors could unlock the root cause to overcome this issue.

Basic Diagnosis

• With the electrical diagnosis, move on to each system’s mechanical components. 

• For steering, inspect the belt-driven pump for leaks or abnormal noise that indicates any internal damage. 

• The high-pressure supply and return hoses must be leak-free. 

• Verify the smooth steering rack operation. 

• On A/C, check the system pressure and look for refrigerant leaks, debris that clogs in expansion valves, filter drier contamination, and for condenser or evaporator fin damage.

Additional Diagnostic Ways to Overcome the Issue

Suppose you’ve worked through all the initial troubleshooting tips and the root causes and still eludes the diagnosis. In that case, there are several more advanced tests to perform.

• Carefully check for any aftermarket accessories that may have been wired into the electrical systems, like LED lights, radios, and chargers. Improperly tapped additions can backfeed the voltage spikes onto critical circuits. Therefore, Unplug and isolate the accessories one by one to test the change in operation.

• Monitor the alternator and voltage regulation system for erratic output. Get a technician to graph the alternator output curve with a diagnostic oscilloscope. This is because bad diodes or failing regulators inside the alternator can misdirect the current away from essential systems randomly. 

• Intermittent issues that don’t set codes require advanced technician-level experience and tools to capture faults as they occur. You’ll have to thoroughly explain the issue’s history and testing trails to the technician. Technical service bulletins from the vehicle manufacturer can also provide model-specific troubleshooting tips. So with, the combination of the owner’s legwork with shop capabilities, this may helps you to get your vehicle back on the road.

FAQs About Power Steering and AC not Working

Q: How much will repairs typically cost?

A: From $200 up to $2000, it may depend on the issue. Mainly, fixes like a fuse or battery or multiple components requiring replacement like pumps, alternators, and computers can go up to these prices.

Q: Is this a DIY fix, or should I have a technician to diagnose it?

A: Due to the electrical complexity and the mechanical speciality tools requirement, you need to have advanced skills, time, and patience in order to diagnose this issue professionally.