Minimum diagnostic equipment

[Jon Hart]

Right bit of back ground I work In the technical support department for a vehicle manufacturer within the uk and after some rather crazy days and stories of dealers not having tools I thought I’d ask the question of what sort of diagnostic equipment the average Main/franchised dealer would have over in the states ( Company I work for has many vehicles in the states as well)

Some of the things over the last few weeks dealers haven’t had include

Any kind of oscilloscope which seems to be very common especially in smaller dealerships

A smoke machine again very common not to have one

Cylinder leakage tester

compression tester

A flat edge to measure the cylinder/block warpage

A back pin set + a D.m.m ( Dealer wanted help chasing an electrical fault 😆 )

Now this is maybe 2-3 weeks worth of excuses and I cant see any reason why any large dealership wouldn’t have these other than the fact that the management of dealerships are greedy and expect the techs to fix things using magic and pixy dust.

Topic

[Andrew Harris]

I am a small independant shop. I dont have the luxuary of sqeezing of the trigger on the parts cannon at every car that comes through the door. Thats not diagnosing cars. Thas replacing parts untill you get lucky enough to replace the right one. I have to tell my customers what is wrong with their vehicle and be right to the best of my abilitys 100% of the time. “Well its probably this” is not an option for me. Every customer is valuable and the way to earn their buisness and keep them coming back through my doors is to be fair, honest and most importantly fix the problem the 1st time.
I can think of numerous examples of when you would need a scope to make you accurate and time efficient when diagnosing problems. Intermittent misfires where the intake covers the cylinders,Relative compression test, timing chain/Belt alighnment on engines where physiucally verifying timing is labor intensive. For that matter any intermittent problem that has to be diagnosed. The scope will catch it if you are smart about what circuits you are testing based on your symptoms. Now am I saying I use a scope to diagnose every car. Absolutly not. What I am saying is that when the time comes to fix the problems others cant after all the parts have been replaced and the problem still remains and the vehicle ends up in my bay the scope becomes a very valuable tool.

[James O’Hara]

Electronic relative compression tests are built into most manufacturer scan tools they are also not very accurate for determining which cylinder it actually is in my experience anyway. Intermittent missfires unless the coil is hiding under the intake cover i would still use a inline bulb first, hell most of the time adding that if it is a gap issue will normally add enough load it won’t spark. As for injectors i normally use a mechanics stethoscope. Timing adv is also normally listed in manufacturer scan tool as is cam position. You can also monitor both of those as you do a relative compression so you can see whether it is off or not.

Good to know that if I decide to go independent it is what I can use it for. I guess I am spoiled having been in dealerships that way. There are a lot of tests that are built into the tools.

I am not firing a parts cannon. I narrow it down to 2 things. There is legitimacy to doing it the way I do. Labor rate is 120/hr. I can replace the part in 5 mins and know if it will fix it or I can pull out the computer, boot it up, hook to the car/truck, have it detect the car/truck, connect to the module go to the activation part, hook up my dmm or scope, run the test and monitor the results. 20 mins vs 5 mins @ 120/hr not to mention if it does fix it, the piece is normally at least half way if not all the way installed where after that 20 mins I still have not removed either part. Why 5 mins cause either way to get to the part you are going to have to take the same stuff apart in most cases.

There are times where pin point tests are great such as testing injectors before you remove the valve cover on a engine where the intercooler and air filter are both mounted to it. Sure then pin point tests it is. Vast majority of the time though the difference is 4 bolts and swapping parts. In a dealership it is no problem doesn’t fix it we just return the part to out parts dept. If you have to order like an independent would then going your route makes sense. That is one of the differences between dealerships and independents.

[Andrew Harris]

Yeah I don’t have a parts department to run to, to test with parts. For me If I were to do that I would have to order the part wait 30 minutes for them to bring it and then test then if it didn’t work I have to send it back and then make sure it gets credited to my account at the end of the month. More headaches than its worth. I used to be a GM dealer tech. Life is sometimes much easier sometimes not. I can honestly say I have learned so much more from being a independent tech. I get to work on so many different makes and models with different issues. I’m not saying your methods are not valid. I am saying that there is a place for Lab scopes and once you learn to use them they make you so much faster and more accurate. I don’t have a factory scan tool for every make we work on. Most aftermarket scan tools do not offer relative compression testing. I know the Tech2 did not. Since were on the subject I find relative compression testing is pretty accurate. I just used it the other day to diagnose a Saturn L300 that had 2,4,6 cylinders no compression. Timing on other bank was good. Belt slipped due to some sort of failure of one of the pulleys behind the timing cover. I haven’t pulled cover. Car isn’t worth the extra diag. needs a motor anyway. Took me all of about 2 Minutes to perform that test.

[James O’Hara]

Might be the way the dealer scan tools do electronic relative compression vs actually doing them by hand /w scope. By hand with a scope you can see everything and overlay multiple graphs dealer scan tool it just gives you a bar graph for each cylinder the percentage of contribution. Far less useful and the computer determines which is what cylinder piss poorly i might add. Though if you see you have cylinders out of wack you still have to pull stuff to replace if you are going to repair anyway and at that point you can actually determine which is bad so….

[Duane]

Before I went to work at a tool manufacturer I spent 20 years in a Lincoln/Mercury dealership. The only tools the shop provided were the ones required by Ford, or as they were called “E” tools (essential). Anything else we had to buy ourselves. We had no scopes and no one had their own. As far as scopes go, they’re great for advanced diagnostics, but most diagnostics can be successfully completed using the pinpoint tests in the shop manual. Most OEM pinpoint tests call for multi-meter use, as they only look at resistance and voltage. I’ve only run across a couple OEMs whose pinpoint tests use scope waveforms and they are Kia and Toyota. They’re included as additional data for known good waveform comparison, but they also use voltage and resistance for testing. Once in awhile I would run pinpoint tests that after checking voltage and resistances would say to replace the PCM and that would not fix the problem. It didn’t happen very often but a scope would have probably found the problem. Scopes are the new fad now because the cost of them have come down to the point they’re affordable by most techs. If you still had to pay thousands of dollars for one and it was a hassle to set up and run, no one would be using them.
The next, newest fad now is thermal image cameras. I see more use for one of these than a scope.

[Bobby]

I think things like Multi-meters, Test leads, Test Lights things that you need to do solid basic electrical stuff.
As for Testing kits, I personally think every tech should have a Fuel Injection Pressure testing kit, a Radiator pressure tester, a basic compression tester.
Things that you could certainly make use of is a Battery tester, a Decent Code Reader (something that will give you freeze frame data), an Ammeter or Low amp probe and a PowerProbe (at least a PP3).
Last would be stuff that an advanced Diagnostic tech should have. Scopes, The More advanced Scan tools (assuming you’re not at a dealer) leak down testers and vehicle specific kits, things of that caliber fit in here.

[Dave]

Hi,
In Canada most dealers did not have an oscilloscope.
Some did not have a compression tester, few had a cylinder leak tester.
None had a straight edge.
None that i worked for had a smoke machine.
The one brand of dealer did not approve smoke just a nitrogen test system and soap or ultrasonic sound tester.
It became worse in some of the small dealerships because the franchisor would send all kinds of specialty tools that were not optional (some are hardly needed) causing the shop to neglect buying useful or essential tools that are not part of the mandatory dealership tools.
It is sad that the techs are coerced into supplying what is needed in order to be able to do their daily job.

[Author]

Replies