Cruise control not working

[rdm21740]

I have a 2000 Mazda b4000 4x4. I have factory cruise but it hasn't worked since I got the truck in 2012 with 234k miles. How do I troubleshoot the factory system? I do know my steering wheel switches are good. I just don't know about the rest of parts under the hood.


Sent from my iPhone using Tapatalk

 

[adsm08]

The first thing to check is the switch screwed into the end of the brake master cylinder. Is it plugged in, is it leaking?

If it is unplugged or leaking the system will be disabled. If it is leaking go to the nearest dealer and ask them for the leaking switch recall kit. It's actually cheaper than just buying a new switch.

 

[rdm21740]

this is what I've found

there is no switch screwed into the end of the master cylinder. there is not even a spot for a switch to screw into. could maybe they replaced the master cylinder with the wrong type? there is a plug near the MBC that is dangling but i could never find out where it goes to. it is a two wired plug one wire is black/yellow the other is green/red. there is also a plug that goes into the reservoir. the truck does have all the equipment for CC (i.e. servo, cable, wiring, steering wheel pods and all wiring inside

 

[adsm08]

Looks like you have the wrong mc. That is the plug for the switch I was talking about.

Postin' from teh Galaxy

 

[rdm21740]

Well I found my first problem. The previous owner put the wrong Master Brake Cylinder on it. It is not for trucks equipped with CC. Once I replace that I will then check the rest of equipment. I do have new wheel switches. I replaced them cause my old ones were all tore up. I did try to check system with the diagnostic check I found on one of the forums. But the truck didn't respond to it. I'm guessing because the CC release switch isn't connected to the MBC since the previous owner put the wrong MBC on. I don't see the recall repair done to my truck. So I guess I need to see if the dealer will still honor the recall due to age and mileage of truck. What's the best way to check the servo motor or electrical. My fuses and TB Cable are both good


Sent from my iPhone using Tapatalk

 

[Earl43P]

Jumper the two pins in that connector, insulate the jumper from shorting anywhere, and cruise should work if all else is good.

 

[rdm21740]

Ok I will try that when I get some free time this week


Sent from my iPhone using Tapatalk

 

[adsm08]

It's a variable resistance circuit. IIRC open means no good, shuts it off. Completely closed means brakes are on. I don't think shorting will make it work right either.

 

[rdm21740]

Ill try the jumper to see if it works. I will eventually replace the MBC,Might as well since I have replaced everything else but the hard lines running to the rear brakes


Sent from my iPhone using Tapatalk

 

[Earl43P]

Fact is, it's a pressure switch, variable nothing.

Brakes pressed, it's an open circuit.
Brakes released, it has continuity.

It is a secondary circuit in case the Brake Pedal Switch fails.
Power from Fuse 13 passes through this pressure switch to Pin 9 of the Speed Control Servo.