Cruise Control

[n2soccer21]

Hey guys,

My cruise control recently stopped working. I almost exclusively used it during highway driving to and from college and I really miss it...Does anyone have any idea why it went out and what can be done to fix it?

Thank you.

1995 SHO 3.2L Automatic

 

[ohfosho]

if you have noticed your steering is feeling weird also, then you could pinpoint the problem to the VSS in the tranny. you can also start easily by pulling codes, and checking your fuses

 

[n2soccer21]

No, the steering feels fine, so I hope that means it's not the VSS in the tranny...whatever the VSS is. I'll check the fuses tomorrow. If I still don't find a problem I'll check the codes. Thanks.

 

[projectSHO89]

Check the cruise disconnect switch on the bottom of the brake master cyclinder. Remove the plug and install a paperclip into the harness connector and see if the cruise now works. Pretty common failure on the ATX SHO.

If that doesn't get it, I have the factory diagnostic procedure available to be emailed upon request.

Steve

 

[n2soccer21]

You know, I thought that may have been part of it. I replaced the master cylinder about a month ago. The new one wasn't exactly the same as the old one in that it didn't have that connection. So I just put a paperclip in there and it's alright? Is it a problem that the new master cylinder didn't have that electronic connection? Thanks a lot.

 

[n2soccer21]

Yup, that was it. I put a big fatty paperclip in there to close that circuit and it works now...thank goodness. Thanks a lot guys.

 

[DavidWatson]

Hope I can revive this thread. Would that procedure be the same for MTX? I have a '93 and cruise just stopped, fuses are fine and no codes relating to it. My indicator light doesn't even come on.

 

[Mels]

Hey now fellas, correct me if I'm wrong but isn't the purpose of that switch to interrupt the cruise upon braking?

Something about driving with that function bypassed seems seriously wrong to me.

The paperclip no doubt makes for a fine troubleshooting tool, but that's as far as I'd go with it. Get the correct master cylinder in there.

 

[projectSHO89]

Mels,

That switch is the backup/redundent cruise cancel. Primary cancel is still the brake light circuit.

David,

The MTX uses a very different system compared to the ATX's system. The ATX is all electronic, the MTX has a electronic/vacuum system that uses a vacuum dump on the brake pedal as its equivilent to the SCDS. As a matter fact, check there for a vacuum leak as it will disable the cruise.

Steve

It does NOt have the SCDS

 

[Mels]

Whew! Thanks for the clarification, Steve

 

[Mark in PDX]

On the MTX 2 things can happen, 1 the cable can pop off at the throttle body, or at the brake pedal it can pop off the bracket that holds the vacuum dump (this is right on top of the brake pedal, so dive under the dash to check this first)... Check both visually and see if there is anything there..
Also, if the brake light switch has failed it can **** the cruise.. I had that happen.. It wouldn't turn on w/o a working brake light switch.. (or off when it did go on.. that was scarey.. but that was on my 89).

Mark

 

[DavidWatson]

ALrighty, I'll have to check that out. My brake light switch did fail and has been replaced w/ a part from Autozone about 3 yrs ago. I don't remember anything being different from the original, but will look again. I don't think it's a cable, my circuit doesn't even register with the ON button on the steering wheel. I do believe it's an electrical problem.

 

[projectSHO89]

David,

I posted a cruise diagnostic for the 89 over in the "How do I.." forum. Much of the description cane from the 92 service docs which should be applicable to the 93 MTX also.

Steve