P1850 in ABS Module

B6/7 S4/RS4
#1

Hi, did a full scan of the car recently as I hadn’t in a while and came up with the following in the ABS Module:

18258 Powertrain Data Bus
P1850 -35-10 - Missing Message from ECU - intermittent

I was originally worried it was ECU related but am now thinking I may have f’ed up my ABS wheel speed sensor when doing a front axle swap recently. Does that seem likely given the code is in the ABS module and I’ve no fault codes in the engine module?

There are no other ABS faults, TC light on etc and everything seems normal yet I’ve cleared the code and it came right back.

#2

for any intermittent I clear, rescan, drive 80-100 miles, rescan… if it doesnt pop back up I dont worry about it

#3

I cleared it last night and then drove to work this morning (20kms) and lo, the f’er was back. I cleared it after I parked and will scan again tonight when I get home.

#4

huh well thats a bummer. I’d try reseating the ecu connector if youve had the box open. you could also try touching the battery cables together (ie remove them from the battery and touch them together, it will discharge everything and sometimes helps exercise electrical demons)

#5

THe ECU was out a few months ago for a tune. I’ll check there 1st I guess.

#6

also, do you have a timestamp to go with the code? may be worth keeping track of if it keeps popping up.

#7

JPO

I wouldn’t worry just yet. The ABS module and the TCU module Seem to have issues when it comes to communication. If its been wet out in your area or extremely hot this can cause communication issues with the ABS.

I can’t say why, I would just say. Give it a few weeks and then try again.

#8

I have this code on all ECU’s that are tuned, it shouldn’t trigger a CEL, doesn’t affect drivability either

#9

Interesting, I haven’t any drivability issues either and no CEL.

#10

This is a good thing. Might have just been a short communication error.

#11

I scanned the module today and no codes. It’s been about two weeks since I cleared them. I’m gonna forget about it until such time as it won’t let me (hopefully never).