As a health reporter who devours medical journals like other people take vitamins - one a day - I usually have no trouble understanding whether doctors know what's they're talking about, or are exaggerating their skills and credentials. But when I encounter car repairmen, I am at a clear disadvantage. Thus it was with dismay that I noted my 13-year-old (but fit) Toyota Corolla's air conditioner was producing barely a cool wind, even though at the end of last summer I had refilled it with refrigerant and the fluorescent additive used to detect leakages showed no problem a month later. I drove into the nearby auto electrician's garage that took care of the air-conditioning system last time, explained the symptoms and hoped any leakage could be quickly and painlessly treated. Two different men poked about, adopted a serious tone and declared: "This is a big problem. Your compressor is leaking. It can't be repaired. It will cost you NIS 3,000 to replace it, and it will take the whole day. We will let you pay it in installments." As the bill would have been a hefty chunk of my journalist's salary, I decided to take the advice I usually give when somebody asks me whether they should accept a doctor's diagnosis of a serious condition: "Get a Second Opinion! SO I found an auto electrician who also fixes car air-conditioners. He looked under the hood, scanned the tubing with a blue light to detect leakages of fluorescent additive and pointed at a completely different part, which he claimed was responsible for the leak. This, he said, would take hours and cost NIS 700 to replace, including a refill of refrigerant. And how was my compressor? I asked gingerly, fearful that he would discover another leak. "It's fine. No problem." The price had come down, but I still was suspicious. My regular auto mechanic, asked for a recommendation, said he wouldn't name a place because he was "likely to get complaints in the end." But he did give me a valuable piece of free advice: "Don't go to an auto electrician who also repairs air-conditioners. Go only to a person who specializes in them," he said, without naming names. That was actually the advice I had gotten from my husband in the first place. A scan of the Yellow Pages produced a short list, with most of them on or near Rehov Harechev at the end of Jerusalem's Talpiot industrial zone. Oddly, the street numbers there are almost totally absent, and when I did find them they went up and then down. To my dismay, two more repair shops self-listed in the Yellow Pages as expert in car air-conditioners were in fact auto electricians who also repair cooling systems. One, which had a sign claiming expertise in speedometers, had glued on the word "Air-Conditioners" at the bottom as an afterthought. The owner listened to my problem, didn't even ask me to turn on the air conditioner, said it would cost NIS 100 for a "test that could take a few minutes or an hour-and-a-half" and added that he couldn't predict what the result would be. I decided to seek out a Fifth Opinion. AN INVISIBLE angel dispatched my car toward David Mazganim, at No. 4 Rehov Harechev, which is accessible via a small alley behind the street. Almost empty of customers that Friday morning, the rather dingy garage was manned by David himself, who was sitting at the entrance. He was wearing a black kippa, had an unshaven look due to the post-Pessah Omer period, and his assistant was a thin man with a long rabbinical beard who was wearing a Shabbat white shirt under blue overalls and an even bigger black kippa. I noticed a shelf of holy books in the garage. Although looking like God-fearing Orthodox Jews is today not necessarily a guarantee of being honest, I relaxed a bit, especially as a sign stating that David was "authorized by the Transport Ministry to repair vehicle air-conditioners" was posted on the door. David offered me a cold drink while I waited. The assistant, whom David called Matok Sheli ("my sweet"), turned out to be David's brother-in-law, who has been studying for the rabbinate but wanted to learn a profession even if it meant he had to get his hands (literally) dirty. "These are my kind of people!" I thought to myself, remembering the rabbis over the centuries who insisted on pursuing a manual vocation in addition serving as spiritual leaders. Every time he asked his brother-in-law for a screwdriver and he brought it to him, David said "please" and "thank you." They forced air under pressure into the system, shpritzed soapy water onto the tubes and found a leak at the top of a part they called the "dryer." When I told him about the first four places I had visited, the varied diagnoses and prices, David said: "I am the only Jerusalem garage owner with a Transport Ministry authorization to fix air-conditioners. But lots of people say they can fix them. There are a lot of cheaters." I sincerely believed him. Matok Sheli , who clearly knew what he was doing, dismantled the grill and then a headlight to make the dryer accessible. While David put on his tallit and tefillin and said the morning prayers, the brother-in-law took out the metal part, polished it like a silver kiddush cup and replaced two valves. His hands were full of soot, but he didn't seem to mind. David finished his prayers, helped put everything in place, and an hour after I had brought it in, he told me the charge: NIS 25 for each of the valves, NIS 250 for a refill of refrigerant and fluorescent stuff, and the rest for the work. The total: NIS 346. My lesson: Whether you need surgery on a body part or a major repair on your car, always seek a second opinion. I can't vouch for the integrity and incorruptibility of the president of Israel, the prime minister, the finance minister or a slew of MKs, but there is one thing I know: "David Airconditioners" is an honest shop.