Wideband O2 related subpage of MembersPage/VasilisP
Conclusions
- WBO2 works - no "wideband problem"
- sensor calibrates fine (if proper LSU4.2 type is selected as it was configured originally)
- although usually (the more available) LSU4.9 is sent with AAN, (the more expensive) LSU4.2 was sent in this case, because "LSU4.9" was NOT chosen (neither in chosen option, nor in ordercomment), and the explicitely requested old 1.2.11 config to upload had LSU4.2 (so only 4.2 provided 100% compatibility, although easy to configure type in new fw; LSU4.9 not selectable in old fw )
- False information (additionally, refusing basic checks) => drawing insane amount of support resources (on user side also, and elsewhere, perhaps also having children)
- ECU works
- is well within specs (including output voltage)
- ECU has nernstpullup, so compatible with LSU4.9
- new 1.2.3x fw also works, it's just that VemsTune should be newer than fw, or at least ini-s must be newer (Preferences / fetch ini files from web)
- [10581_AAN_running_Vemslogs.zip] provided by owner.
- showing that engine is running
New ECU (v3/10581 AAN with NTC MAT input, oid 10875); config file uploaded as requested in the order comment without any change => config not changed in any way; the LSU4.2/LSU4.9 option was not changed, left at the correct LSU4.2, as LSU4.2 was shipped.
- Paper would be included with any LSU4.9 sensor, instructing to check that 4.9 is configured (but LSU4.9 paper is not included with LSU4.2 , as in this case).
Please note that [ECU with motronic55] (the controller contains the 27k nernstpullup and is compatible with both LSU4.2 and LSU4.9) can be ordered with accessories:
- "loom for LSU4.2" which is compatible with [LSU4.2] and very old fw.
- "Loom for LSU4.9"
- "with_LSU4sensor: yes", THIS WAS ACTUALLY ORDERED, which means unspecified either LSU4.9 or LSU4.2
- Although usually LSU4.9 is provided if unspecified, for compatibility with new 1.2.31 fw and also the old fw 1.2.11 (user requested to upload config saved from 1.2.11) => LSU4.2 sensor was actually provided with this order, and there is nothing wrong with that (ECU was also configured LSU4.2 ; with the exact config uploaded as requested in the order comment)
User reported that
- he received LSU4.9 sensor and he cannot calibrate perfectly (just to 20.1% O2, not to 20.9%), which is no surprise for an LSU4.2 configured wrong (as LSU4.9)
Since than user made a new order and purchased LSU4.9 sensor, we included the SSC5-LSU4.9 loom for no extra charge.
Upload ini file - note: VT ini-s must be uptodate
When using new fw (eg. 1.2.31), VT must have all the new ini-s for it (preferrably the latest).
- Use the newest VT (nightly, or [dev])
- AND "Preferences / fetch latest ini files from web"
- that might be the step why uploading old config to new fw shows so good fuelpw match on bench (for many-many testcases), and it ends up slightly rich when uploading without up-to-date ini-s (which can still be tuned of course, but more work).
New ECU-s (including AAN) have protection diode on all outputs (not just injector, ignition, stepper, but also including the p259/x outputs incl. p259/0 tachout). The output is within spec (0-14V), and has no adverse effects. Has absolutely no effect when injectors are powered (when fuelpump and engine running).
- with key turned to ignition on, after fuelpump stops (properly, after the configured amount of time), before the engine starts , the rev meter jumps to above 2000rpm and the dash warning lights up the LOW OIL LEVEL. LOW OIL LEVEL is unlit (as it should) when starting the car, and RPM shown correctly.
- so the low oil-level is unlit when engine is started and oil-pressure is present (good)
- the RPM tacho also shows correct value when engine is started, if I understand. Showing 0-7000 RPM is well within the normal function of the dash (be assured, dash won't be harmed electronically from 8900 RPM or higher, or from any 0-12V signal coming in the dash-tach input from ECU),
- and lighting up low oil pressure is very good indication the dash works as intended, similarly to the CEL light, usually lit before engine is started, and actually doing what it was designed for; with no risk of damage (these dashes worn mostly because of solder-corrosion and cold-warm heat-cycling, not because of any voltage input well within the normal voltage range).
No high-voltage or anything similar that could damage the dash.
Protection from p259/0 is removed for no extra charge if requested order time, or if ordering [repair-upgrade] but this, by itself, does not qualify as warranty repair.
Injectors=... cc/min, type=... Fuel pressure= ... bar above MAP pressure
I noticed that all my map was too rich
- VT, or at least ini files must be newer than fw, in this case the 1.2.31 fw (so Preferences/update ini files from web), eg. if uploading old 1.2.11 config to 1.2.31 fw
- otherwise some values configured, reported might be misleading (at least once, VT warns about this: "fw newer than VT").
If config was uploaded with newest VT and after Preferences/update ini files from web, and still think it became (very unlikely, many many benchtests and real tests showed: uptodate tools => good result) significantly richer (under similar conditions, eg MAT, CLT), we'll verify and investigate. If possible, point us to ...sec and ...sec time positions with comparable input-vector but more than 1.5% difference in injpw/(MAP*VE*req_fuel * enrichments).
After lotsof time wasted, it turned out the report of not working with "LSU4.9" configured was simply caused by actually using LSU4.2
- When i calibrated the WBO2 for the first time the 4.2 was selected, I calibrated the lambda sensor and used 214 number to achieve a 20.9 air calibration.
- and considering latest info, and loom pinout matching LSU4.2, that is be perfectly correct (and than anything with LSU4.9 setting is on the wrong track and explains many things)
with bogus LSU4.9 setting for an LSU4.2 sensor, during calibration, it peaked at 255 showing 20.1% O2 in free-air.
- note: this might not always be the exact symptom
- but almost certainly, an LSU4.2 sensor will NOT heat up to target "cherry-red" temp if configured as LSU4.9 (although an inexperienced installer might not notice the internal temp, from the glow-color, looking into the sensor)
Useful measurements - in the rare case if there are problems even if the correct type is configured
- Share your measurement of the sensor Rcal = ... Ohm ? with DVM.
- do you have another sensor (LSU4.9 or LSU4.2)?
- I have a 4.2 lambda sensor lightly used. If i am to recalibrate should i clean it?
- is it possible the sensor was dropped (eg. to concrete floor) ?
- SENSOR WAS NOT DROPPED!!!!
Not relevant here, but could be useful in some special cases
- if WBO2 calibration is configured lower than optimal (eg. forgot to calibrate, out of negligence, or emergency; and this turned out later), the WBO2 reading is still REPRODUCIBLE.
- So (although more work), conclusion can be drawn from vemslog captured with wrong (eg. too low) calibration value. It means that lower deviation from 1.0 lamda is displayed (lower than the real 20.9% O2 value is displayed; and higher than real lambda value displayed (example):
| lambdatarget (=lambda reading) | desired lambda (real lambda) |
| LR | LR, or LR-0.01 below 0.9 |
| 0.79 | 0.78 |
| 0.80 | 0.79 |
| 0.81 | 0.80 |
| 0.82 | 0.81 |
| 0.83 | 0.82 |
| 0.84 | 0.83 |
| 0.85 | 0.84 |
| 0.86 | 0.85 |
| 0.87 | 0.86 |
| 0.88 | 0.87 |
| 0.89 | 0.88 |
| 0.90 | 0.90 |
| 0.91 | 0.91 |
| 0.92 | 0.92 |
| 0.93 | 0.93 |
| 0.94 | 0.94 |
| 0.95 | 0.95 |
| 0.96 | 0.96 |
| 0.97 | 0.97 |
| 0.98 | 0.98 |
| 0.99 | 0.99 |
| 1.00 | 1.00 |
| 1.01 | 1.01 |
Eg. -0.01 under 0.9 lambda formula (example only!) to compensate the miscalibration.
- it does not even prevent closed loop feedback EGO/lambda mixture control. VT can be configured to compensate, or another sensor can be used of course.
The key to success is measurements (even if just a few and simple in this case, they are important).
Possible measurements
- perhaps all is good, as the vemslogs indicate...
- the sensor might be faulty (we usually do NOT heat the sensor, the sensor is tested by the manufacturer - Bosch in this case). But according to logs (and even calibration) the sensor seems to work and respond well.
- or perhaps the SSC5-LSU4.2 (or SSC5-LSU4.9) small loom might have wires swapped, or perhaps all mirrored ? (we test the v3, and the manufacturer of the loom tests the loom, we just supply that from the shelf).
- we test the v3 carefully before sendout, but of course nernst or pump HW problem cannot be completely ruled out (or misconfiguration, which we should verify also from vemscfg / vemslog).
- No indication of problem found in vemslog
Besides the measurement, write the SSC5 pin number and the wire color for each pin (and the wire-color at the LSU4 sensor !), and verify connectivity and pin-correctness of the small SSC5-LSU4.9 loom according to the [LSU4.9 pdf].
- sensor type: LSU4.2 or LSU4.9 ?
- is it in free-air, not in exhaust ?
- DC voltage between SSC5/pin4 pump- and GND ? (4V or so ?)
- SSC5/ ... ? loomwirecolor/sensorwirecolor ?
- DC voltage between SSC5/pin1 nernst and GND, if 1k (or other, 1..100k documented value) resistor is connected between nernst and GND ? Near 1/(1+27)*5V = 0.179V ?
- SSC5/ ... ? loomwirecolor/sensorwirecolor ?
- DC voltage between SSC5/pin2 heater+ and GND ? (12V or around?)
- SSC5/ ... ? loomwirecolor/sensorwirecolor ?
- DC voltage between SSC5/pin3 heater- and SSC5/pin2 heater+ ? Can you see the sensor internally glow to cherry-red and get warm, and slightly smell while the voltage climbs up above 6..9V when WBO2 calibration is started ?
- SSC5/ ... ? loomwirecolor/sensorwirecolor ?
- optional measurement if NOT already diagnosed by the above. DC voltage between SSC5/pin5 pump+ and SSC5/pin4 pump-, with 100 Ohm between pump+ and nernst; and 100 Ohm between nernst and pump-?
- SSC5/ ... ? loomwirecolor/sensorwirecolor ?
- is your wiring from ssc5 to wideband connector verified and known good ?
- My wiring is as sent from VEMS shop (good pinout for LSU4.2):
| SSC5 | LSU4.2 | color | wirecolor inside sensor |
| 1 | 1 | black | ... |
| 2 | 3 | thick red | ... |
| 3 | 4 | brown | ... |
| 4 | 5 | blue | ... |
| 5 | 6 | thin red | FILL THESE IN |
Checked and verified
Wrong for LSU4.9 and correct for LSU4.2 ! See [aan_doc.pdf]
New looms have wires matching Bosch colors, not just the nernst and pump+, but other wires also (eg. yellow for pump-, as in the sensor).
Are you sure ? Is it the new LSU4.9 cable with small WBO2 connector ?
- unfortunately Bosch changed the pin numbering => do NOT use "WBO2" when talking about the connector, use "LSU4.9" or "LSU4.2"
- when trying to calibrate your sensor, does it get warm ?
- It does
- could you make a vemslog of wideband calibration warmup cycle (let it run for 4-5min) and add the vemslog to your page here for review.
Using the provided information i will provide hints on how to proceed.
Log review (Dave) [10581_AAN_running_Vemslogs.zip]
- first log does not contain warmup data, but small engine start in the end engine running fine
- second log contains warmup sequence, heater and pump control all confirmed good lsu 4.9 selected in config, o2 reading almost spot on (with wideband calibration 214) i am not sure what the guys problem is; as far as i can see wideband control is working perfectly
- v3.3_u010581-2015.09.03 09h
- 3d log review has engine running (idling) wideband warmup, running exactly the configured lambda target 1.02 with ego 100-101% i have yet to see the first log of it not working
- 4th log some throttle blipping car seems stationary, otherwise no problems apart from way too much cold accel add (and mult)
See FileArea (how to upload files). Generic instructions on MembersPage