Display Groups 007 & 008
DISPLAY OVERVIEWVAG 1551 Display Overview, Display Group 007:
VAG 1551 Display Overview, Display Group 008:
TEST TABLES
Test Table, Display Fields 1 - 4:
Notes on Display Field 1:
^ O2S control should only be evaluated after successful learning (see learning requirement display), both in "Basic Setting" function 04 and in "Read Measuring Value Block" function 08.
^ O2S control displays the momentary control status. After successful learning (see learning requirement display), the values vary around 0.0 +/- 6.0%. If the learning process (display field 4) is ended and value 0.0% +/- 6.0% has not been reached, see display group 010, display fields 3 and/or 4 and check the control behavior of the two oxygen sensors. The display values should occasionally drop below the value 0.3 volts and exceed 0.6 volts. If not, check the Heated Oxygen Sensor (HO2S) heater and Heated Oxygen Sensor (HO2S) probe.
^ O2S control stop evaluation performed by diagnosis also proceeds only after successful learning, see learning requirement display: control stop max.: +29%, control stop min.: -60%
^ If values exceeds 20% in "Basic Setting" function 04, air leaks and/or engine damage (oil burning due to piston damage) are possible.
Notes on Display Field 2:
In display field 2 (learning range display), the momentary learning range (load status) is displayed. Only Closed Throttle Position (CTP) and partial load learning ranges are displayed since no learning takes place at Wide Open Throttle (WOT).
To obtain the appropriate learning range (load status), perform the following steps:
^ For CTP, Start engine and let idle (must be between 700 and 900 RPM)
^ For partial loads 1,2, and 3, test drive vehicle using a second person. Increase the engine speed to 1500 - 3000 RPM while simultaneously loading the engine by lightly applying the brake.
Interpreting The 4-Digit "Learning Range Display"
Key To Learning Range Display:
Value "0" = Engine Speed (RPM) and/or RPM and load not reached for this learning range.
Value "1" = Engine Speed (RPM) and/or RPM and load reached for this learning range.
Notes on Display Field 3:
^ The O2S learning requirement diagnosis shows what O2S learning value was checked in the learning process. When diagnosis is complete, the corresponding value is set to "1" regardless if the diagnosis was recognized as OK or not OK.
^ If "Oxygen Sensor learning requirement diagnosis" value is set to "1" in display field 3 but the corresponding "Oxygen Sensor learning requirement display" (display field 4) is not set to "1", the diagnosis will be performed but not recognized as OK.
^ The O2S diagnosis is reset to an engine coolant temperature less than 40°C (104°F) for each start.
Interpreting The 8-Digit "Learning Requirement Diagnosis"
Key To Learning Requirement Diagnosis Display:
Value "0" = Diagnosis not performed.
Value "1" = Diagnosis performed.
Notes on Display Field 3:
Display field 4 (learning requirement display) shows in what learning range (display field 2) learning requirement is needed
Requirements for learning:
^ No malfunctions stored in DTC memory
^ Engine speed must be between 700-800 or 1500-3000 RPM.
^ Engine coolant temperature (ECT) must be between 80° 105°C (176-221°F) (If learning does not start immediately after this requirement is met, depress the accelerator pedal)
Learning is prohibited if:
^ Engine speed (RPM) is uneven (hunting), during acceleration and with wide open throttle
^ Malfunctions are stored in the DTC memory (does not apply to sporadic malfunctions)
^ A 9% difference is present between the richest and leanest O2S learning values in one display group. If a 9% difference is reached, the continued learning of both affected learning ranges is adjusted. The learning requirement display of these learning ranges then cannot be 1 -> display groups 005 and 006.
Learning starts 20 seconds after initiating "Basic Setting" function 04 and/or 2 to 4 minutes after each engine start in which the engine coolant temperature (ECT) is less than 40°C (104°F).
The following key shows when the requirement for new learning (learning requirement) is forced:
^ After initiation of "Basic Setting" function 04 with VAG 1551 ST all learning requirement displays are set to 0 in order to force new learning of all O2S learning values after repair
^ After each start, with ECT less than 40°C (104°F), learning requirement is forced in all learning ranges
^ If there is a large learning value deviation (from stored learned value to the newly learned value) in one learning range during the learning process, all learning requirement displays are set to 0 again
With successful learning, the learning requirement values of the respective learning ranges (display field 3) are set to 1.
Interpreting The 8-Digit "Learning Requirement Display"
Key To Learning Requirement Display:
Value "0" = Request for new learning.
Value "1" = Learning process ended for the moment.