A motronic55 install might save some time making a harness, but you must always verify the harness reasonably carefully.
This involves
- measurement of all used pins
- mostly DVM ohm-mode
- sometimes voltage mode
- visual inspection
- the injector part of the harness receives much heat. Insulation might be worn. It's better to fix ASAP, than to risk engine damage.
Make your own page for your measurements like MembersPage/TormasiAudiAan, using this as a template. Steps:
- click "Edit this document" for this page
- click "Edit this document" for your MembersPage
- copy/paste the template from this page to your memberspage
- edit on your memberspage
- you can delete these steps (you've just done)
- add your measurements
- save your memberspage
- save from time to time, don't risk losing many hours of edits. You can also keep snapshot of unsaved changes in a local file, especially if the browser you use is abbreviated as msie.
- close this page (without saving)
Documents and files to use
- [ motronic-AAN-ECxx.xls pinout spreadsheet]
- neglect column A (that was the first motronic55 ECU, nonstandard pins for wastegate control and carbon canister)
- this is the most important docs, so you know pinout and function mapping. In MegaTune you will see names like EC36pin10 while you have it wired to some motronic pin. While you do the measurements, write the measured value and the pin you used, and any notes you think appropriate
- AAN starting config and tables: [HL install]
- this uses alternate=04 that is alternate injector firing even during cranking. alternate=14 (that is batch firing injectors during cranking, obviously with lower cranking pulsewidth cwl and cwh values) is more common except for extreme big (1600cc) injectors.
- CHECK that IGNITION OUTPUTS match h[2] (cyl1 and cyl3 were originally swapped)
- note that better tuned fuel and ignition was made for 3B engine (and successfully applied to AAN as well), see MembersPage/MarcellGal/PowerAndTraction You will also find config/tables (where req_fuel=1E that is 3.0 msec) for 680cc/min (727cc@4bar==680cc@3.5bar) injectors with RON98 gasoline (way too little fuel for the factory injectors) so check that, do NOT apply blindly
- firmware 1.1.27 from [here]
- 1.1.24 or later (higher RPM limit, even for a bit uneven 135-tooth wheels) is config-wise compatible with 1.1.23, except h[2] must have (hexadecimal) 38,48,58,68 for stepper A,B,C,D (so 36,46,56,66 will NOT activate i259 not s259 output! )
- temperature calibration tables from EasyTherm
- coolant: NTC type 1900_256 or 2063_256 is a very good starting point when nonstandard NTC sensor is used with weak 2700 Ohm internall pullup
- MAT: PTC type 260_425 is a good starting point when the factory PTC type MAT sensor is used with the default strong 430 Ohm pullup (for some reason the 260_425 was more precise for us than 260_430)
- MegaTune (1.1.12 or later)
- latest v3gui.exe also [available here], useful for firmware upgrade
- 1.1.1- can be used for logging, if your USB-rs232 adapter windows driver freezes, see MegaTune
- normally you have some preference at the time of order, like MembersPage/TeppoKalske (page bottom). Also consider that the crew who built and tested your device might have updated it!
Sensor measurements
Measure sensor resistance against AANpin30.
- ... Ohm between 44 and 30 (MAT)
- ... Ohm between 45 and 30 (CLT)
Injector and idle-air output measurements
Measure injector and idle air pins against AANpin37 (that is the flyback pin, same function as EC36pin23 in standard VEMS docs)
- inj cyl1
- inj cyl2
- inj cyl4
- inj cyl5
- inj cyl3
Ignition outputs
Check the spreadsheet (link above) with all the pins.
- cyl1 AANpin1, EC18pin11 StepperD (0x66) mdn03
- cyl2 AANpin2, EC18pin5 StepperC (0x56) mdn02
- cyl4 AANpin20, EC18pin10 StepperB (0x46) mdn01
- cyl5 AANpin21, EC18pin4 StepperA (0x36) mdn00
- cyl3 AANpin23, EC36pin11 ignch4 (0x40) mdn04
So this is old standard (with AANpin1 and AANpin23 swapped as in the original doc, only very few were made this way):\n
h[1]=00 48 36 24 12 00 00 00 h[2]=36 46 56 40 66 50 50 50
good: 40<=>66 (ign for cyl1 and cyl3) swapped and (for compatibility with 1.1.24 and later:) all .6 changed to .8:\nÿ2ÿ
If in doubt, just remove sparkplug high-voltage wires (easier if 1 at a time). make a small 1mm gap to ground (with a wire or a sparkplug) and issue mdn04 mdn03 mdn02 mdn01 mdn00 spark-test to see if cylinders fire in the right order
- after you upload config, of course (so the h[2] table is filled in properly)
- recommended to do this for all 5 cylinders as an end-to-end test
- see TerminalProgram and GenBoard/MenuSystem on how to issue mdn.. commands, although you can do it from MegaTune tools/serial-terminal as well (say "Man" first).
Grounds
Measure that grounds are strongly (max 0.1 Ohm) connected inside the VEMS ECU.
- AANpin10
- AANpin19
- AANpin24
- AANpin30 sensor ground
- AANpin48 trigger ground
Measure ECU pins: verify that all the above grounds are connected inside the ECU.
Measure that first 3 are connected in the harness. AANpin30 (sensor ground) and AANpin48 trigger ground are likely not connected inside the harness.
Trigger
The secondary trigger crankhome-VR MUST BE reversed. Can be done in the connector on the firewall.
Measure trigger resistance against AANpin48.
- ... Ohm between 49 and 48 (135 cranktooth-VR primary trigger)
- ... Ohm between 47 and 48 (crankhome-VR secondary trigger)
Reversing crankhome-VR polarity
- Disconnect the crankhome-VR secondary trigger (3 pin AMP connector at the firewall). In the female connector:
- measure with DVM that one of the 3 pins go to motronic AAN pin48 (this is trigger GND)
- measure with DVM that one of the 3 pins go to motronic AAN pin47 (crankhome-VR secondary trigger. The 3B engine-harness pinout is different: 3Bpin49 !!!)
- measure resistance between the relevant 2 pins in the 3pin male connector. You should get the same Ohm as above (eg. 980 Ohm)
- swap the 2 wires in the female connector (red and violet in our case)
- if you cannot pull out the receptacles, than you need to cut, blank, solder and insulate
- mate the crankhome-VR secondary trigger 3pin connector (male in the female :-)
- do the measurement in the motronic pins, ... Ohm between 47 and 48 : it should still be the same (the ohm measurement is polarity independent)
Location of the trigger plug:
Wiring crank home normal:
Swap the red and violet wire:
The wire is swapped:
HALL signal
- ... V between pin8 and pin 30 (this needs ECU plugged in and ignition on so the ECU outputs +5V to pin12)
- changes between 0 and 4..5V as the engine rotates (push the car in gear5)
WBO2 on SSC5 male standard applies to both Audi AAN and 3B (also to BMW):
- pin1 nernst,WBO2 pin 1
- pin2 WBO2 pin 3 (use a 5A fuse from +12V supply wire)
- pin3 heater(-),WBO2 pin 4
- pin4 pump(-),WBO2 pin 5
- pin5 pump(+),WBO2 pin 6
OBSOLETE SSC4 male WBO2. was used before 2007-08 (now SSC5 is used)
- pin1 nernst,WBO2 pin 1
- pin2 pump(-),WBO2 pin 5
- pin3 pump(+),WBO2 pin 6
- pin4 heater(-),WBO2 pin 4
- Remember that WBO2 pin 3 must get heater+ from a 5A fuse from +12V supply wire ! The WBO2 heater+ does not come from the ECU (only the WBO2 heater-)
AAN ECU extra connector pins:
SSC6 feemale
- pin1 mcp3208 pin6,ch5
- pin2 mcp3208 pin7,ch6
- pin3 mcp3208 pin8,ch7
- pin4 EC36 pin 34 (power out)
- pin5 EC36 pin 36 (power out)
- pin6 GND
3B ECU extra connector pins: AS YOU LIKE
3B note: motronic55, pin1 is EC18pin11 (stepper-D), see pinout
IF YOU USE DISTRIBUTER and one ignition output to control spark for all 5 cylinders, you must limit dwell in config. To allow high spark energy at 1.5+ bar boost especially above 7500 RPM, distributorless ignition (or CDI) is needed.
SSC6 feemale for 3B... unspecified
- pin1
- pin2
- pin3
- pin4
- pin5
- pin6 GND (use pin6 for ground if you want ground at all. You can also require that pin6 is an analog input or an output)
Note that there is NO best, one-pinout fits all pinout for 3B. The 3B extra pinout is made as requested in the order note.
- Sometimes more ignouts (power or logiclevel) are desirable
- other times more analog inputs.
eg.
- 4 outputs and 2 analog inputs might be a good choice (allows 5coil setup).
- 1 ground, 3 inputs, and 2 outputs allows distributorless ignition (not an everyday setup, but it works)
- cyl1 driven by factory coil (motronic55 pin 1 and the factory ignition power-output stage and coil)
- cyl2,5 and cyl3,4 driven by a 2x2 wastedspark ignmodule (logiclevel or power inputs)