PDA

View Full Version : cruise control, switch or relay symoptoms?



jent
03-14-2005, 07:48 PM
My cruise has desided to not work any longer. It has been a process. For a while it would work or wouldent, seemed kind of random. And now it just will not work at all. I was thinking it sounds like a failing switch since it did not just go, it went gracefully. Is that a right assumention, when the relay goes does it just work one day and then not the next? How can I check if it is the switch or the relay? if you need any more information just let me know.

absolute
03-14-2005, 08:01 PM
ten to one odds it's the control unit.They get bad solder joints inside and fail intermitantly.

jent
03-14-2005, 08:05 PM
Originally posted by absolute
ten to one odds it's the control unit.They get bad solder joints inside and fail intermitantly.

is the control unit the switch? never heard that term before, sorry for the confusion.

cbass
03-15-2005, 09:29 AM
I'm having a similar problem with my cruise control. I heard that on the older a4's it was a vacuum type system that was harder to diagnose. Mines a 98.5 1.8TQ tip

jent
03-15-2005, 06:16 PM
so, I was driving home form work. And for some reason I tried the cruise control. AND IT WORKED. I was exctied, sweet a ride home with the cruise. While driving the cruise desided to dis-engage just while driving stright. So, since it disengaged while nothing else changed would that not be more likely a relay failure? Just something new to add to the pot....thanks in advanced

Hassmeister
03-15-2005, 06:35 PM
Mine gave up the ghost a few months ago. I assume it's the stalk or brain near the glove box. I don't need it right now with all the near town driving. Come Summer I'm doing some diggin'.

absolute
03-15-2005, 07:00 PM
Originally posted by jent
is the control unit the switch? never heard that term before, sorry for the confusion.
the control unit is above the glovebox inside the dash. It is the "brain" as stated above. I have replaced or resoldered(internal connections) atleast 5 or 6 in the last year on 97-99 a4s . 3 times I thought I could blame the switch but every time it turned out to be the control unit. It's not a cheap gamble around $300 new but you're showing the exact symptoms.
good luck[up]

jent
03-15-2005, 08:03 PM
sorry for being so ignorant....but the control unit is something diffrent than the relay that rest behind the glove box also? again sorry

edit** i looked in the bently manual and the only thing I see it the control module located behind the glovebox, i assume this is what you are talking about. I am really suprised about the $300 price tag, is there anyway with a multimeter to check to see if this is the issue, or possibly just cleaning the contacts or something since someone said the contacts are really poor. I just can not beleave this is a 300$ issue when it seems so simple. Thanks for any input

Hassmeister
03-15-2005, 10:47 PM
[confused]

absolute
03-16-2005, 06:09 AM
Originally posted by jent
sorry for being so ignorant....but the control unit is something diffrent than the relay that rest behind the glove box also? again sorry

edit** i looked in the bently manual and the only thing I see it the control module located behind the glovebox, i assume this is what you are talking about. I am really suprised about the $300 price tag, is there anyway with a multimeter to check to see if this is the issue, or possibly just cleaning the contacts or something since someone said the contacts are really poor. I just can not beleave this is a 300$ issue when it seems so simple. Thanks for any input
that's the one behind the glove box/above the glove box. if you remove it, take the cover off, look close at all the solder joints on the circuit board you may find some that are cracked. Resolder them and give it a try. If it still doesn't work time for a new one.[:(]