Cruise on 9000CSE

I also had cruise problems.Re-soldering the computer did nothing. Replaced it from a junker and the the cruise works again. The computer replacement was the last thing to try. First make sure there is no vacuum leaks, then replace the computer. Good Luck.

On most CSE cars 94-> (don't know about the '93, but think is is old school), the cruise is totally unlike the C900 or early 9k (vacuum pump unit). It is totally electronic with a stepper motor or some such running it. If I am not mistaken, its brains are in the trionic Engine ECU. It could be pedal switches, brake light on, wiring, or the stepper motor. I have one of these which I could part with for the right price.

KeithG

ajs wrote:

Thanks for the reaction Keith, bu my CSE still works with the vacuum pumt under the hood... And it is a 9000, not a C900. The ECU is from Hella; pedal switches are new, and the brake light circuit is well OK. It's weird that the system works fine on higher environment temperatures, and doesn't work below approx. 72 degrees F.....

Hmmm, Interesting. I just went out and verified that I was not smoking crack. My '97 CS (and I think my previous '95 CS) has the electronic Cruise... The stepper motor is right behind the battery. The EPC says this was changed for 1995-98 to be the electronic unit.

Speed control ECUs

9000 up to 87 95 60 905 88/89 95 26 757 >1991 95 26 757 1992 41 08 650 1995> 44 33 108

As I said, interesting. Sorry for the mis-direction. I am looking a US EPC. The 1995> part number looks like the stepper motor I am referring to. It must also have the electronics in it as well so that it is mostly a stand alone system. This EPC does not show a vacuum pump on the 95>. I just assumed that it was connected to the Trionic.

If yours is the earlier style >

I have a weird problem with the cruise control on my 9000CSE (1994). The whole thing works fine when the outside temperature reaches about 22 degrees Celsius (about 72 degrees Fahrenheit), or direct sunlight for a longer period of time. I have checked all of the components, replaced the pedal switches, even took out the electronic control unit and soldered all circuit point again, but nothing seems to help. Outside temperature down.... No cruise control. Anyone a clue??? TIA Rob

Hey Rob. .. from my experience (20 years messing about with hi-fi amplifiers), if a problem is so temperature dependant then 9 / 10 it is a bad solder joint or hairline crack in a pcb track or an electronic component failing (I know you've gone over it with an iron but these things can be almost impossible to see). I remember sharing a flat with a guy who had to blast his tuner with a hair dryer for a couple of minutes every time he wanted to hear the radio! Don't know if you could swap ecu's just to see??

Anyway - good luck '93 Saab 9000 CS

Thanks, Bob... I guess í will try to resolder the whole unit.. A replacement ECU is not done here in Holland.... I just can't get my hands on one, not even at the two specialised Saab junkers in my country... I guess they break down a lot!.

All of you, thanks for the advice; i'm going to heat up my iron... ;-)

Cheers Rob

"Nasty Bob" schreef in bericht news:uVKYc.83672$ snipped-for-privacy@fe1.news.blueyonder.co.uk...

Keith, to be more specific: It is the Hella 41 08 650....

Rob

"KeithG" schreef in bericht news:0qGdneJ2DORdF6 snipped-for-privacy@wideopenwest.com...

"KeithG" schreef in bericht news:0qGdneJ2DORdF6 snipped-for-privacy@wideopenwest.com...

Thanks guys, i resoldered every single component, and it seems to work again. Temperature outside now about 15 degrees Celcius, and the CC works fine again. Problem solved????? I hope so!!!!

Rob

Thanks guys, i resoldered every single component, and it seems to work again. Temperature outside now about 15 degrees Celcius, and the CC works fine again. Problem solved????? I hope so!!!! Rob

Cool! ;)

Cool! This is further motivating me to try this trick on my 1992 900. As to the ECU location on the 1992 900:

The last time I had the lower dash removed, I saw a silver, vertically mounted box on the driver's side (LHD). It had a wiring harness connecting to it from the bottom, I think. It didn't have any clear markings indicating what it was. I pulled the circuit board out, and the only thing remarkable about it was a tiny relay of some sort on the board, which could snap open or shut (via a spring and presumably a magnet).

Is this the right thing? The Bentley manual isn't especially clear on this point.

John

John, It surely looks like the right one! Be sure to let the little spring on the small relay in place!

Rob

"John B" schreef > > Thanks guys, i resoldered every single component, and it seems to work

Sounds great! Good work! It sounds similar to the C900 unit, then.

KeithG

Rob wrote:

Ok, I spent some quality time with my cruise ECU and a soldering iron yesterday afternoon. I started at the wiring harness connectors, and worked my way down the circuit board, un-soldering and re-soldering every point. When I was about halfway done, I put it in the car and gave it a try, and it still didn't work, so I was having my doubts about the project.

Anyway, I finished re-soldering everything anyway. I got lazy towards the end and started simply melting the existing solder and letting it re-set. When I was finished, I was so sure it wouldn't work that I didn't bother to test it.

So when I was driving to work this morning, it got its first test... and it worked flawlessly! For the first time in about five years, my cruise control works reliably! And even better, the repair came at no monetary cost. Thanks so much to everyone who provided help on this topic. This problem had been bugging me for a long time.

John

1992 900S na