We have a 1995 Volvo 850 turbo sedan (222 hp, ~170k miles, bought it new). When I start it in the morning or after a long parking time (i.e., more than 7-8 hours long) the ABS and Tracs lights come on (and stay on); the ABS first and a few moments later the Tracs one. When I start our car after having it parked for, say, less than 3-4 hours, none of the ABS+Tracs lights ever comes on (and they stay off). This pattern started a few days ago. The only ABS code I get is 444 (i.e., no power supply to hydraulic modulator valves). Any suggestions on what may be happening and/or what to try next?

Thank you very much for your comments, again. It turns out that an increasingly malfunctioning alternator killed one battery and it tried to kill a second one, before a correct diagnosis was made. Now, a 'new' alternator later, the ABS + Tracs lights no longer come on and everything is normal. There seems to have been some sort of connection in there. Thanks again.


1995 Volvo 850 turbo sedan (222 hp, ~170k miles, bought it new), the best car ever driven by "yct" on both sides of the Atlantic (excluding only truly exotic cars worth $150k+)

every time the abs/tracs acts up that i've seen, it always posts a code/s for lr wheel sensor, abs pump or both. and THAT means a module. the 444 i've not seen before, but i will say that i have seen a similar problem on the same vintage bmw and THAT car got the ecu and the module to fix that. volvos do not have an ecu for the abs. but i'm willing to bet, you need the typical 850 abs module. don't know if it's worth your while to have the abs tested and make sure the 444 is legit or an abs module ghost. good luck, chuck.

The ABS pump is a $2000 part! So don't bother with going to a dealer.

Startt by cleaning the connection to the ABS pump, just unplug it and use an old tooth brush and clean bot the male and female sides with electrical cleaner. Check the wiring near the plug to make sure the wires haven't broken with age.
While you are at it, clean the MAF plug, it needs it.

Nice fun car, I just sold mine last summer at 95k miles.

Klaus
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Just driving a 1998 V70R :)