Parasitic drains can be measured with ammeters with the battery cable. Now the problem with taking the battery cable off to install the ammeter is that, sometimes electronic modules are the source of the parasitic draw. In this technical tip clip instructor Dave Hobbs talks about some other tricks for diagnosing these problems. He talks about the class two message monitor– a feature available on the Tech Two and also the Master Tech– it basically tells which module’s active and which module is inactive. He also goes on to cover using a parasitic draw tool in order to not disrupt the circuit while using an ammeter. Watch this clip to learn how to use the class two message monitor and or a simple knife switch that can actually be used for some neat tricks in diagnosing some stubborn, hard to find, parasitic battery drains.
In this tip clip from the Vehicle Stability Control class, instructor Dave Scaler measures the DC bias voltage of a wheel speed sensor and shows you how understanding these sensors will make active wheel speed sensor testing much easier.
In this short video clip from the A4 Suspension and Steering class, Delphi instructor Dave Hobbs discusses and shows some basic tips and knowledge to help you better diagnose alignment issues based on tire wear helping you more quickly and accurately use the alignment machine to put everything in spec.
Watch this tip clip excerpt from the A4 Steering and Suspension ASE Test prep course presented by Dave Hobbs. Dave talks about proper testing and maintenance of power steering fluid and related components–showing examples and highlighting the things you should know both as a technician and to pass the ASE A4 certification test.
Check out this technical tip clip on CAN Data with Dave Hobbs. In this clip Dave talks about Class 2 layouts, specifically the ‘loop configuration’ systems. He breaks down the layout of theses systems in an easy to understand manner and talks about how the modules communicate on this type of system as well as how they are electrically wired.
In this tip clip, Dave Hobbs talks about what to do if you have a vehicle with no PCM data. You plug in your brick, and you go to pull codes or look at PIDs in this late 90s, whatever, early 2000 Chrysler. It’s got CCD. You think you’re talking on the CCD. You’re actually talking on SCI, and scan tool just sits there and says no communications. What could the problem be? Is it a bad scan tool? Bad computer? Bad bus wires? Well, in this clip Dave gives some quick pointers on what to look for next.
In this case study with Dave Hobbs, we learn about the complexities and challenges of diagnostics of data bus systems. Dave talks about a Chevy Malibu he once worked on: it couldn’t start several modules. He talks about how, sometimes, bus issues can be things you would never suspect and how keeping up with learning about these systems and understanding their complexities is necessary if you want to work on cars with these problems.
[pre_ad postid=”7876″]On May 26, 2011 Motor Age hosted the second of four live, interactive training webcasts scheduled for 2011. Sponsored by Delphi and Motor Age, several topics were covered including a brief discussion of HFO1234yf, proper sealant and refrigerant identification methods, proper oil charging and compressor care, and lots more.
In this hybrid vehicle tech tip Dave Hobbs talks about an ‘engine stop request code. If you’ve got a hybrid vehicle and you’re not sure– is it doing an idle stop or is it just stalling– because we have still have an internal combustion engine and that means we still have all other kinds of sensors that can cause drivability issues, including intermittent stalling conditions. Thats why Dave talks about the engine stop request PID and how it can keep you from chasing the boogeyman.
In this Tip Clip Dave Hobbs talks about EVAP and FREDS, you know Frustrating Ridiculous Electronic Devices, things like PCM’s and ECM’s. He talks about the logic of how these devices control the operation of the vehicle’s evap system. He discusses how the ‘brain’ of the evap system handles things like the operational nature of the evap system such as purge. He also goes into detail regarding how the FRED also handles the regulatory side of things such as EPA guidelines and leak tests.
Dave Hobbs presents an interesting case study of a Chevy Malibu exhibiting battery discharge issues, no start problems and with a B1516 BCM code. Dave discusses the associated TSB and smart charging system components related to this issue.
Alternate Uses For Your Evap Smoke Tester: tips and tricks for many different uses of and evap smoke tester with Dave Hobbs