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Hi, this is Susie Thompson. You had my car for a week and when I picked it up yesterday you told me the car was fixed and charged me $350 for the repairs. Now I am stranded because my car just broke down again. What are you going to do about this?. What’s going on with this car?
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Hi, this is Susie Thompson. You had my car for a week and when I picked it up yesterday you told me the car was fixed and charged me $350 for the repairs. Now I am stranded because my car just broke down again. What are you going to do about this?
What’s going on with this car? I test drove it up and down the street and around the block. I was sure the problem was fixed when the MIL did not turn on again. I know the old part was defective and I am sure the new part is functioning properly. What’s wrong with this?
How could I have reduced the chances of a comeback to a minimum? How could I have seen the actual data the PCM used to make its decision? What is Mode $06? What is the $ sign all about?
OBDII Diagnostic Modes Mode 1: Data Stream Mode 2: Freeze-Frame Data Mode 3: Diagnostic Trouble Codes (DTCs) Mode 4: Clear Codes & Freeze Frame Data Mode 5: Oxygen Sensor Monitor Mode 6: Non-Continuous Monitors Mode 7: Continuous Monitors Mode 8: Bi-Directional Communications (Onboard Tests) Mode 9: Vehicle VIN, PCM Calibration Etc.
Terms Used in Mode 6 Data • TID = Test Identification • CID = Component Identification • TLT = Test Limit • Hexadecimal: Example:( $0032) • Raw Data • Manufacturer’s Conversion Factor • Test Value • Results • Limit Type
I/M Monitors ( One not complete) Illustration 2 in manual
I/M Monitors after DTCs cleared Illustration 4 in manual
$$$$$$$$$$$$$$$$$$ Hexadecimal numbers are often used by computer - types in place of the base ten numbers you and I use to count our money and balance our check books. Hex (for the number six) and decimal (for the number ten) combine to form a numbering system that is base 16. Hexadecimal numbers are also alphanumeric since they’re made up from combinations of the numbers 1 - 9 and letters of the alphabet from A - F. Counting to 16 in hexadecimal goes as follows: $01, $02, $03, $04, $05, $06, $07, $08, $09, $0A, $0B, $0C, $0D, $0E, $0F and $10. Zero is still zero, and is used only as a place holder to indicate – you guessed it – nothing! Using this combination of 16 characters, the computer guys can list all numbers from 1 thru 255 using only two digits. (Funny, but that’s the range often used to describe fuel trim, with 128 being the midpoint! See! It does have a use.) To convert a two digit hexadecimal number to base 10, multiply the left number by 16 and add that to the hexadecimal value for the right number. See following examples.
$$$$$$$$$$$$$$$$$$ Counting to 16 Decimal Numbers – Right The Decimal number 17 is represented by the Hexadecimal Number – Left hexadecimal number 11. $1=1 That’s 16X1 plus 1 X 1 = 17. $2=2 $3=3 Let’s try one more. Convert $E6 to decimal. Since $E=14 $4=4 and it’s in the “16’s” column, we need to multiply 14 X 16 $5=5 and then add 6 from the right column to get the $6=6 decimal equivalent. $7=7 $8=8 (14 X 16) = 224 + 6 = 230. $9=9 $A=10 Using only two hexadecimal digits, we can count all the way $B=11 to the decimal number 255. $FF = (15 X 16) + 15 = 255. $C=12 $D=13 The decimal number 256 is equal to $100 in hexadecimal. $E=14 That’s (1 X 256) + 0 + 0 = 256. $F=15 $10=16
Courtesy of Ford Motor Co. Illustration 9 in manual
Mode 6 data – 2002 Ford Focus – EGR monitor TID - $49 CID $30 Test Value 34471 ($86A7) Test Limit 33536 ($8300) Test Value: Manufacturer’s Conversion Factor – 34471 – 32768 = 1703 x .0078 = 13.28 in. H2O Test Limit (Minimum): Manufacturer’s Conversion Factor - 33536 – 32768 = 768 x .0078 = 5.99 in. H20 Raw Data – 32768 times .0078 equals total vacuum/pressure difference in inches of water. (in. H20) with EGR closed. This test limit has a value of 6 inches of waterminimumpressure difference between the pressure registered at point one and that measured inside the intake manifold. Actual pressure difference: 13.28 in. H20 Minimum pressure difference: 5.99 in. H20 --- EGR monitor passes test.
1998 Ford Ranger 2.5 liter engine Illustration 3 in manual
1998 Ford Ranger – 2.5 liter engine – (4 cylinder) • TID $10 – CID $21 is catalyst monitor for bank two. This vehicle has only one bank and thus this data must be disregarded. • TID $10 – CID $11 is catalyst monitor for bank one. This is the proper data to be used to check the efficiency of the catalytic converter. • TID $10 CID $11 Test value ($001D) converted to decimal = 29 raw data. Manufacturer's conversion factor = 29 x .0156 = 0.4524. This number can be rounded off to .45. • TID $10 CID $11 Test Limit ($0036) converted to decimal = 54 raw data. Manufacturer’s conversion facture = 54 x .0156 = .8424. This number can be rounded off to .84. • In this case the maximum allowable is .84. The actual test results are .45. • The minimum efficiency allowed is 100 - 84 = 16%. The actual test results show an efficiency of: 100 - 45 = 55%. This indicates the converter will pass the mode 6 monitor test, however, it is only 55% efficient in storing and releasing oxygen. So if the vehicle fails HC emissions and all other factors have been eliminated, a new OEM converter should solve the problem.
TID $04 CID $02 HO2S Heater Circuit Mode 6 Data Captured by Scanner Conversion Factor supplied by Manufacturer 8337 x .000076 = .633612 (Amps) (Test Value) 2621 x .000076 = .199196 (Amps) (Minimum Value) Heater current recorded is good for the proper operation of the HO2S when engine is first started. The current is recorded on initial startup of the engine. The maximum level is displayed in mode 6. As the sensor increases in heat, the resistance increases with a resulting decrease in current flow. This heated HO2S helps the fuel system to go into closed loop operation sooner, thus reducing cold startup emissions. It also prevents the system from going into open loop during extended periods of engine idle.
TID $05 CID $01 EGR Monitor Mode 6 Data Captured by Scanner Conversion Factor Supplied by Manufacturer Test Limit: 64x0.625 = 40 – 40 = 0 (Degrees Centigrade) Minimum Allowable Test Value: 96x0.625 = 60 – 40 = 20 (Degrees Centigrade) 20 deg. C above In this case the increase in temp. caused by exhaust gases flowing through the EGR valve must be at a minimum of 40 degrees centigrade. This EGR system is causing an increase of 20 degrees centigrade above the minimum. In other words the increase is 40 + 20 = 60 degrees centigrade. If the temp. increase is too little, it could be caused by a partially plugged EGR port.
TID $01 CID $01 Catalyst Monitor Mode 6 Data Captured by Scanner Conversion Factor Supplied by Manufacturer 10 x .0039 = .039 Actual Reading 128 x .0039 = .4992 Maximum Allowable (Approximately 50%) 100% - 50% = 50% minimum efficiency allowable 100%- 4% = 96% Efficient (Actual Efficiency of Catalytic Converter)
TID $06 CID $01 Air Fuel Ratio Sensor Mode 6 Data Captured by Scanner Conversion Factor Supplied by Manufacturer Test Value:0x0.000244 = 0 Test Limit: 20480x0.000244 = 4.99712 This is a measurement of the response time, of the A/F sensor, when the PCM richens the fuel mixture. If the response time is 5 or greater, the monitor fails the A/F sensor. If the sensor is close to failure it will not set a code. However, the efficiency of the converter will be decreased and could cause an emissions failure.