Author & Automotive Expert James D. Halderman

 

 

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Halderman newsletterNovember 2012

Welcome to the November edition of the Halderman newsletter.

 

II always enjoy hearing feedback and I am always willing to listen. Hearing some feedback about what people want from my website made me want to alter it. I'm happy to say that my website has been redesigned to be more user friendly. Please check it out. See the story below for an update on the webiste.

And thank you from the bottom of my heart for the encouragement and feedback.

 

I've enjoyed connecting with you many of you on social media and look forward to future correspondence on Facebook, LinkedIn and Twitter.

 

Sincerely,

Jim

IN THIS ISSUE
Redesigned Website
Tech Tip
ASE Sample Question
Straight Talk
Testimonial
Have you seen the new Jameshalderman.com?

 

 

My new website has been redesigned and is more user friendly.

New highlights at jameshalderman.com are:

- New pull-down menus make finding content easier

- Expanded content now includes 2,000 videos and over 300 animations (FREE)

- Photo library that has over 1,000 photos that can be sued in Power Points for classroom use

- Links to Pearson's website for instructor resources including Power Points, Test Banks, and task sheets

Tech Tip

Think of Money

Digital meter displays can often be confusing. The display for a battery measured as 12 1/2 volts would be 12.50 V, just as $12.50 is 12 dollars and 50 cents. A 1/2 volt reading on a digital meter will be displayed as 0.50 V, just as $0.50 is half of a dollar.

It is more confusing when low values are displayed. For example, if a voltage reading is 0.063 volt, an auto-ranging meter will display 63 millivolts (63 mV), or 63/1,000 of a volt, or $63 of $1,000. (It takes 1,000 mV to equal 1 volt.) Think of millivolts as one-tenth of a cent, with 1 volt being $1.00. Therefore, 630 millivolts are equal to $0.63 of $1.00 (630 tenths of a cent, or 63 cents).

To avoid confusion, try to manually range the meter to read base units (whole volts). If the meter is ranged to base unit volts, 63 millivolts would be displayed as 0.063 or maybe just 0.06, depending on the display capabilities of the meter.

ASE Sample Question

Question

Technician A says that a low or zero reading on an ohmmeter indicates continuity. Technician B says that an ohmmeter set on the highest scale and reading infinity means no continuity. Which technician is correct?

 

a.         Technician A only

b.         Technician B only

c.         Both Technician A and B

d.         Neither Technician A nor B

 

 

Answer:

The correct answer is c. Both technicians are correct. Technician A is correct because if the ohmmeter display shows zero or low ohms, this means that there is little if any resistance between the meter leads. The component being tested has continuity and current will flow if connected to an electrical power source. Technician B is correct because an infinity reading, such as "OL" on the display, means that there is such a high resistance between the meter leads that the meter is unable to measure on the highest setting. In other words, the component being measured lacks continuity and no current will flow if connected to an electrical power source. Answer d is not correct because both technicians are correct.

Straight Talk

From the October 10, Wheels section in the Dayton Daily News:

 

The case of the broken transmission

Wheels: Al W. from Centerville asks:

"My 1999 Dodge minivan will shift from first to second gear almost immediately as I start to drive it and then not upshift from second regardless how fast I drive. It stays in second gear all the time. If I shut off the van and restart it, it will start off in first gear but then it immediately shifts into second. I am using a lot of gasoline driving around in second gear all the time. I have talked to other owners and some technicians that they think that the transmission computer has to be reprogrammed. How is this done and what causes the transmission computer to do this? Any help will be appreciated."

Halderman:

Second gear is the default gear if the transmission computer detects a fault in the transmission. The most likely fault is a defective input speed sensor, also called as turbine speed sensor. The transmission will start off in first gear but as soon as the vehicle speed increases and the transmission computer detects that a signal from the input shaft is not available, it will command second gear to allow the vehicle to be driven to a repair shop. Second, or third gear in some transmissions, is called the limp-in or default gear when the computer is not able to determine what is going on. Using the limp-in gear allows the vehicle to be driven yet will not cause any harm either. Ask a local shop to check for any diagnostic trouble codes or monitor the input speed sensor data using scan tool with the vehicle being driven. The speed sensor for both the input and output are a pattern failure item on these transaxles and the replacement sensors are reasonably priced and readily available. The sensors can be easily changed using simple hand tools and the transaxle does not need to be removed to change the sensors.

  

Find more Straight Talk columns here

 

 

 

 

 

 

Testimonials
 Testimonials about the new website

It looks really nice to me. I like the links across the top; easy to find stuff.-Jeff R from Florida

Spent a little time on the site. I like it! Easy to navigate, clean and crisp. I plan to show it in class Monday. -Mike G from Ohio

Looks good-Tom B from California

This looks really great,But this like a great, more orderly update. I am still in awe of the amount of material! Awesome stuff. Joe P from Michigan

Wow, that looks very nice. Better than the last one definitely. Slick. -Brad H from Ohio

  

Do you have a helpful hint? I'm always looking for miscellaneous information and helpful hints to include in my books, presentations and the newsletter. Feel free to email me with your hints, and maybe I'll include it an upcoming newsletter.

 

Please let me know what you think of the newsletter. I would love to include any of your automotive news or any tech tips you might have. Send me your suggestions! 
You can email me here or visit my website. You can connect with me on Facebook, Twitter and LinkedIn too (links above). And I encourage you to visit this website for great car reviews and more of my Straight Talk columns.
Regards,
Jim Halderman
 
James D. Halderman writes automotive technology textbooks for Pearson Education. He is an ASE-certified Master Technician with more than 20 years instructional experience.