94 Cruise Control Problems

[80 Cruiser Rod]

I posted this problem before a while ago along with having read many threads on this subject. The problem is and from what I have read seems to be inherent to some of the older Cruisers. When I turn on and engage my cruise control it lights up in the dash and starts to blink. After 5-6 blinks it turns off. The only way you can turn the cruise control back on is ti restart the truck.

From all that I read about this and from the replies I got from my last post, the best solution and poor mans fix was to disconnect the main connection to the cruise control unit and clean the connectors. After doing this my problem got worst. The cruise control use to work every other time, now it almost never works.

I am hoping with many new older cruiser owners since my last post, maybe someone has come up with a solution for this. Replacing the unit from what I read could cost as much as $2,000, not an option. Replacing it with a used one may and probably will have the same problems. So, if there is anyone out there who has a fix, please step forward.

Thanks,
Rod

 

[Jack G. Nichols]

The Field Service Manual should have a code reference that tells you what the number of blinks mean, and help you diagnose the problem.

I had a cruise control problem that drove me nuts - turned out I needed a new brake fluid tank cap. Fixed it.

And check your brake fluid.

All that is worth about what you paid for it. ;*)

Jack Nichols, 1993 LC

 

[Tyler93]

Bump

the cruise on my 93 is intermittent as well.

 

[Pin_Head]

Pulling the error code would help point you to the problem. Assuming it turns out to be the actuator, you can disassemble, clean and lube the actuator. There is a web site that describes how to do this that has been linked to in several threads on CC problems.

 

[evanz80]

I posted this problem before a while ago along with having read many threads on this subject. The problem is and from what I have read seems to be inherent to some of the older Cruisers. When I turn on and engage my cruise control it lights up in the dash and starts to blink. After 5-6 blinks it turns off. The only way you can turn the cruise control back on is ti restart the truck.

Thanks,
Rod

I had a similar problem on my '93, and it turned out to be the brake light switch. Once replaced, that solved the problem and the cruise worked great.

As I recall, the switch is up under the dash and the brake pedal presses against the switch to activate it. A mechanic found and corrected the problem for me (and it's been a few years ago), so I can't offer much in the way of diagnostic information. But it seems that somehow the brake light switch was part of an electrical circuit that wasn't working the way that it should. If you think about it, it makes sense from the standpoint that the brake pedal turns off the cruise control. Hope this helps!

 

[jonheld]

The replies about fluid level in the reservoir and faulty brake switches, etc do not apply here. If your CRUISE lamp is blinking, the CC ECU is telling you there is an error in the CC system. You must pull the codes and diagnose.

Bad sensors in the cap and bad brake lamp switches will simply disengage the CC. They wouldn't cause a blinking CRUISE lamp.

 

[80 Cruiser Rod]

The Field Service Manual should have a code reference that tells you what the number of blinks mean, and help you diagnose the problem.

I had a cruise control problem that drove me nuts - turned out I needed a new brake fluid tank cap. Fixed it.

And check your brake fluid.

All that is worth about what you paid for it. ;*)

Jack Nichols, 1993 LC

I do have a PDF version of the FSM, I will read through it and see what I can find. You wouldn't happen to know where in the FSM the error code is?

 

[80 Cruiser Rod]

The replies about fluid level in the reservoir and faulty brake switches, etc do not apply here. If your CRUISE lamp is blinking, the CC ECU is telling you there is an error in the CC system. You must pull the codes and diagnose.

Bad sensors in the cap and bad brake lamp switches will simply disengage the CC. They wouldn't cause a blinking CRUISE lamp.

Ca you be more specific about the "Bad sensors in the cap"?

 

[80 Cruiser Rod]

Pin_Head, I read your post back in January. My bad, the last time I posted my problem was a while ago. I should have done another search. I'll try your method when I get a chance along with try to decipher my error code. If I don't get anything with that, I'll maintenance the Cruise Control Actuator. Thanks for your previous post.

 

[jonheld]

Ca you be more specific about the "Bad sensors in the cap"?

Typically, the brake fluid level sensor in the master cylinder reservoir cap becomes intermittant and will cancel the CC. Sometimes it just barely illuminates the BRAKE lamp on the dash. It's enough to cancel the CC, but dim enought to miss in daylight.

Anything brake logic related will cancel CC.

 

[80 Cruiser Rod]

I'll check my fluid level too! Thanks!

 

[Inukshuk]

I diagnosed and fixed my cruise so here is my addition to the knowledge base:

I had a similar problem on my '93, and it turned out to be the brake light switch. Once replaced, that solved the problem and the cruise worked great.

As I recall, the switch is up under the dash and the brake pedal presses against the switch to activate it. A mechanic found and corrected the problem for me (and it's been a few years ago), so I can't offer much in the way of diagnostic information. But it seems that somehow the brake light switch was part of an electrical circuit that wasn't working the way that it should. If you think about it, it makes sense from the standpoint that the brake pedal turns off the cruise control. Hope this helps!

I took my old switch apart. My pictures below show why and where the dual-circuit switch fails.

The replies about fluid level in the reservoir and faulty brake switches, etc do not apply here. If your CRUISE lamp is blinking, the CC ECU is telling you there is an error in the CC system. You must pull the codes and diagnose.

Bad sensors in the cap and bad brake lamp switches will simply disengage the CC. They wouldn't cause a blinking CRUISE lamp.

The above applies if the CRUISE blinks continuously. In my case it would blink and then go dark and throw no codes.

Symptom:
Cruise control light turns on when you press and release the on/off button.
Cruise control light flashes a few times and then goes dark when you try to set the speed.
Attempt to pull a diagnostic code gives nothing.
-- I did all the electronic diagnostics first and everything checked on the stalk and at the actuator. --

FIX:
Installed new stop lamp switch (brake light switch at the pedal). Why this matters: the 1993 with cruise control has a two circuit switch. One is for the brake lights. The other is for cruise control. The brake light part is robust.

The cruise control part is a bent metal contact – mine lasted a mere 300,000+ miles (337,000 today but it started going out more than a year ago). What happens is when the bent metal is worn out, the contacts effective length is shortened and the cruise-control-canceling circuit is "always-on."

OEM for a 1993 80 84340-06010 cost me $63 at Stevinson Toyota online. Aftermarket is available but its a critical safety item so I went OEM. If your 80 cruise lights up but then blinks and shuts off, this is probably why.

Easy to replace once you contort under the dash. A couple 14 MM nuts hold a threaded shaft in the hole. Pro tip: undo the wire connection after you get the switch out of the hole.

 

[Tachycardic]

This thread helped me immensely. I also got the dreaded 5 blinking "cruise" light and decided to adjust the brake lamp switch first before actually pulling the code. I noticed that the brake lamp switch has 2 levels of detents and the way it was adjusted on my truck, the brake pedal only depressed the switch to the first detent (second pic). After adjusting the two 14mm nuts, the brake lamp switch was fully pressed in position (3rd pic) when the brake pedal was in the rest position. This fixed my cruise control. Hope this helps others.

 

[banjo1981]

Just followed all the threads and performed all the recommended diagnostics. Had cruise control code 12. Decided to try what @Inukshuk did and replace the brake switch. All other diagnostics passed when testing the Cc stalk, speed sensors, etc. Replaced the brake light switch with an AutoZone part ($55) and voila! Went around the block and cruise works perfectly. Thanks MUD!