Practical Uses of Mode $06

August 7, 2009

By James E. Wilson. Mode $06 continues to be a hot topic with techs. Nevertheless, there are many techs who have not even heard of Mode $06 or do not even use the Global OBD2 side of the scan data. To get started using Mode $06, pick an area that is easier to use. Knowing how to use Mode $06 could really help in the day-to-day diagnostic problems in your shop. I suggest using the Mode $06 on Ford vehicles in two areas.

Ford Misfires
I’m talking about finding Misfires before they set codes. Use test number 51 on older Ford and 53 on 1998 and newer.
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The formula is to take the numbers and multiply it by 0.000015 to get the percentage of a Misfire.
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The Type A Misfire is 40% at idle and a 4% at high rpm and load. Now can you see why a misfire can cause a problem long before it sets a code?
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Notice the information about the Profile Correction Operation. We will cover this in the second part of the article.
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The Test is 53 and Component 02 that is for cylinder 2. Use the conversion formula to check the test.

109 x .000015 =.001635

This is not enough to cause a code to set, but it might still be a concern. Check these to find the problems before they turn into codes.

Ford O2 Testing
Here I will show you a Ford test for O2 sensors and will pass the O2 sensors for amplitude reading that are above the minimum limit of 563. The normal ranges for a good operating O2 sensor is 800 mV or above. I guess they do not want codes on this sensor.
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Global OBD2 readings converted to Decimal from Hexadecimal.
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The enhanced side of the Genisys gives a text description of the information.
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The conversion factor is the measured reading times 0.00098.

Example:
863 x 0.00098=.84574 or .846 Volts

This test is for an O2 sensor amplitude that needs to go above .5 volts, but we need to look a little further into how the monitor runs. The test is ran by using a special 1.5 Hz square wave fuel routine to drive the fuel mixture around stoichiometry and produce a predictable O2 Sensor signal amplitude. If it does not reach the minimum amplitude of .5 Volts it will set a code for slow response like a P0133 for Bank 1 or P0153 for Bank 2.

You need a proper switching O2 sensor to control the mixture. This monitor test lists amplitude, but actually tests for speed. Now can you see the problems like a P0420 Catalytic Efficiency because we have a slow O2 that does not feed the Cat the proper Mixture?

If you are new to Mode $06, then start with these tests and get comfortable with using the data. Then you can move on to other selection in Mode $06 and before long it will be a regular part of your diagnostic strategy. Part two of this article will be coming soon.

Jim Wilson has over 30 years of experience as an ASE Master Certified technician, fleet technician, shop owner and has worked in training and development for SPX/OTC. AS AVI’s OTC scan tool expert he has taught programs on Genisys, Pegisys, EVO, fuel trim, mode 6 and has been an instructor at the AVI Training Conference.

For more information, visit Jim’s website at www.autodynamicsltd.com, and check out www.auto-video.com for more great training videos!

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