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The benefits of MAP-controlled thermostats

February 9, 2022

A customer driving a 2014 BMW 328i arrived at the college's 2nd-year electrical lab reporting his illuminated check engine light. The customer had no complaints other than the light. The vehicle had just over 82K miles showing on the odometer. A student (Phil) assigned to the BMW performed a review with a scan tool, and a single code (P0597 – Thermostat Heater Control Circuit Open) was present.
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Sometimes it is user error

February 8, 2022

I encountered a situation in the early days of recovery/recycling machines when they had just been introduced.  I had set up a machine about four months earlier when the customer purchased it.  I went to great lengths to cover proper operation of the unit and the shop owner even attended a certification clinic I conducted. 
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Air contamination in an A/C system can ruin your day

February 2, 2022

I had a memorable encounter with air contamination in the mid 1990s.  I was conducting a lot of retrofit clinics at the time and had recently acquired a demo refrigerant identifier which I took to those clinics. At one clinic, there was a technician who was extremely interested in the refrigerant identifier.  
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Long exposure of car driving down highway

MACS changes leadership

January 31, 2022

MACS is changing leadership. Elvis L. Hoffpauir, is stepping down at the end of January 2022 from his duties as MACS president and chief operating officer to enjoy retirement. Following a 42-year distinguished career at the Mobile Air Climate Systems Association (MACS), Elvis will transition to past president and association advisor.
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Heater Insight

January 25, 2022

Recently, a customer brought in a 2006 Honda Insight with a heater that was blowing cold but had no other vehicle concerns. A local garage had informed the customer the head gasket had failed; however, the owner felt a second opinion was necessary.
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Air contamination in mobile A/C systems

January 18, 2022

We covered a base line test conducted with 0% air contamination and provided pressure and temperature information.  This week we will provide pressure and temperature information experienced with 7.7% air contamination and 18.9% air contamination. 
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The effects of air contamination in an A/C system

January 11, 2022

If you perform an Internet search for effects of air contaminated refrigerant on automotive A/C system pressures, you’ll find many results.  This information leaves no doubt that air contamination of refrigerant in an automotive A/C system can affect system pressures and temperatures
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Variable output scroll compressors

January 5, 2022

This compressor has been around for quite some time and the vehicles it is used on are getting some age on them.  However, they still show up in shops with regularity and there still seem to be a lot of technicians that are not aware of the problem, diagnostic procedure and cure. 
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Helping your customer understand their A/C repair

December 16, 2021

To help service shop owners, MACS has created a 30-page consumer guide for your customers that explains how their car’s engine cooling system and air conditioning system works. “Getting to know your car’s air conditioning and engine cooling system,” details how these vital climate systems work and why they may require an extensive repair.
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You can get Tesla repair information

November 10, 2021

Find out how to use Tesla software for aftermarket repair
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Troubleshooting the “what ifs” in a mobile A/C repair

November 9, 2021

High side:  Likely somewhere around 130 psi (at an idle) & 140 psi at 1500 rpm.  Why? With only a 35% charge in the system, the compressor isn't going to be producing a lot of pressure.
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Meet MACS member, Tom Lech

November 8, 2021

Stationed in San Francisco, California, Thomas Lech has maintained a bustling business for almost three decades. Lech Auto Air Conditioning has been busy for 365 days a year from opening at 7 a.m. to closing at 7 p.m. for the last 27 years, with summertime only increasing the demand for the shop’s services.
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