Understanding your car’s health goes beyond basic OBDII readings. Accessing Mode 6 data, also known as On-Board Diagnostics Monitoring Test Results, provides a granular view of your vehicle’s emission system performance. Pairing an Android Obdii App With Mode 6 capability unlocks a wealth of information for both car enthusiasts and professional mechanics. This article delves into interpreting Mode 6 data, using a real-world example to illustrate its power.
Decoding Mode 6 Data: A Practical Example
Let’s analyze a sample Mode 6 query result:
0600 => 7E8 06 46 00 80 00 00 01
This response indicates which Parameter IDs (PIDs), or Monitor IDs (MIDs) as they are referred to in Mode 6 for Controller Area Network (CAN) vehicles, are supported. This specific result shows support for bits 1 and 32, meaning commands 0601 and 0620 can be used. Since 0605 isn’t supported, querying it yields an undefined result.
A subsequent data request returned:
7E8 10 37 46 01 01 0A 0E 66 7E8 21 0E 66 0E 66 01 02 0A 7E8 22 0E 66 0E 66 0E 66 01 7E8 23 07 0A 00 00 00 00 0C 7E8 24 D8 01 08 0A 1D 70 13 7E8 25 18 22 90 01 09 10 00 7E8 26 78 00 78 05 F0 01 0A 7E8 27 10 00 00 00 00 00 00 Removing the address header and multiframing simplifies this to:
01 01 0A 0E 66 0E 66 0E 66 01 02 0A 0E 66 0E 66 0E 66 01 07 0A 00 00 00 00 0C D8 01 08 0A 1D 70 13 18 22 90 01 09 10 00 78 00 78 05 F0 01 0A 10 00 00 00 00 00 00 This represents six test results, each comprising nine bytes. Breaking down the fourth result:
MID TID UASID VHI VLO MINHI MINLO MAXHI MAXLO
01 08 0A 1D 70 13 18 22 90 -
MID 01: Confirms the requested
0601command, corresponding to “exhaust gas sensor monitor bank 1 – sensor 1” as defined in SAE1979(DA). -
TID 08: Indicates “Maximum sensor voltage for test cycle.”
-
UASID 0A: Specifies the unit and scaling as “Voltage” and “0.122 mV per bit unsigned.”
Calculating the test value using VHI/VLO:
( 0x1d * 0x100 + 0x70 ) * 0.122 = 919.392 mVSimilarly, the minimum and maximum values are 596.336 mV and 1079.456 mV, respectively. This indicates a successful test.
OBD2 Expert Component Monitoring Mode 6 Diagnostics
Leveraging Mode 6 for Advanced Diagnostics
An Android OBDII app capable of decoding Mode 6 data offers significant advantages. It allows users to:
- Proactively identify potential issues: Mode 6 provides insights into component performance before noticeable symptoms appear.
- Perform targeted repairs: Understanding specific test results allows for more efficient troubleshooting and repair.
- Verify repair effectiveness: Mode 6 confirms whether a repair has successfully addressed the underlying issue.
By utilizing the power of Mode 6 data through a compatible Android OBDII app, car owners and professionals can gain a deeper understanding of their vehicle’s health and performance.
