APY narrowband to wideband conversion


Registered User
Mar 16, 2019
Reaction score
I'm about to convert my narrowband APY ecu to a wideband ECU. I've done a fair bit of research regarding this topic but i still have some uncertainties i needed to clear up. First of all the ecu im getting will be from a AUM 110kw or ARX 110kw or AUQ 132kw or ARY 132kw because i cant find any BAM or AMK at the junkyards in my country, and even if i do they will charge me upwards of 500 euros for an ecu and lambda. The engines codes i listed are all wideband but i'm not sure about the EGT.

I compared all the wiring diagrams side by side and found some differences (attached are APY and AUM diagrams for the ECU). In blue i marked all the components that my APY does not have and the ones the AUM won't have since i will be getting the ecu from a vehicle with a manual transmission. In yellow i marked all the common pins, in red the pins they don't share between each other and in green the uncertainties i needed to clear up.

1) VVT
according to this thread all i need to bypass the vvt is a 15ohm 25 watt resistor. Or alternatively i can get it coded out... i just need to find a good specialist in my country.

2) Lambda
according to the wiring diagrams i need to make the following changes:
Existing harness->New wideband sensor plug
Pin 52 on ecu->wideband sensor Pin#6
Pin 71 on ecu->wideband sensor Pin#2

3)F88 power steering switch
if i understand the diagrams correctly, the AUM from September 2000 has a F88 switch connected to pins 49 and 50, however from MY 2001 it doesn't have one. Photos attached. All 3 other engines have it in both years. Does that mean i can't use an AUM ECU because it doesn't have an F88? or could it be a mistake in the wiring diagram?

4)ECU pin 61
On all 4 ECUs the pin 61 is not connected anywhere (normally goes to the EGT sensor on the AMK and BAM) but on the APY ECU it's connected to the J293 Radiator fan control unit. Is there any known solution to this?

5)J234 Airbag control unit
On all 4 ECUs the pin 67 is connected to the J234 Airbag control unit, however, on the APY, this pin is not connected to the J234, it's not connected to anything. Do i need to run a wire or just leave it disconnected?

As per the wiring diagrams, none of the engine codes i listed have an EGT sensor, so nothing complicated there.

Thanks in advance


  • APY.pdf
    1.5 MB · Views: 296
  • AUM from 2001.pdf
    1.8 MB · Views: 131
  • F88 - AUM 2001.png
    F88 - AUM 2001.png
    89.3 KB · Views: 108
  • F88 - AUM 2000.png
    F88 - AUM 2000.png
    148.6 KB · Views: 104
Last edited:
Did you find out the pin61 ?as i swap from apy to bam and now the fans from are workig from Putin the ignitoin on
did anyone get this swap done?
Also looking at APY to AUM conversion.
What need to be done to get this to work?
Can the car be started with the AUM map and be driven to tuner after conversion?