Chevy SSR Forum banner

1 - 20 of 23 Posts

·
SSR Overseas, Ireland,
Joined
·
387 Posts
Discussion Starter #1
Hi
Have issue with cruise control not engaging. Have checked with Tech2 and switches seem to work ok, only issue I can see is that the “Stop lamp pedal applied”. Now the pedal switch is working fine as when applied the brake lights come on. Is there a second switch for cruise control?
 

Attachments

·
GOD BLESS OUR TROOPS
Joined
·
1,762 Posts
Multi Switch Operates - Cruise Control, High Beams, L-R Turn Signals, Windshield Wipers and Washer Fluid. That's a lot of components in a small device. If you need to replace it, It's EASY to install, either have someone help you that has replaced one before and or follow the instructions on the forum.

My Cruise was intermittent on a long drive. I bought one from Dictator and a couple months later I had to replace it as well. I found another switch on line.

https://www.am-autoparts.com/Chevy/SSR/turn-signal-switches-and-levers/AM-38479392/321521.html?gclid=Cj0KCQiAp7DiBRDdARIsABIMfoCZSQL9xjd7bcHrUWzzD8MufN7jUjOkH10sZfa-dsvG2rIwYqEwKI8aAoarEALw_wcB

I have LEDs all around, since I changed the switch the last time I haven't had any problems for over a year.

I hope it doesn't come to that.

Good Luck
 

·
Genuinely SSR Obsessed
Joined
·
8,370 Posts
Hey Irish. Besides your cruise control trouble I hope you've been getting along fine. :smile2:

Sorry I don't know much about the cruise control as I live in a huge traffic filled world here in Houston so I rarely get to use it. :frown2:

I'm sure someone knowledgable will jump in soon.


images-37.jpeg
(Something like this would be sooo much easier!!!)



★★ - Good luck to you!!




==============
David :black:
2019-01-17-08-47-59--1550734631.jpeg
 

·
Daily Driver
Joined
·
8,941 Posts
Have you changed to LED lights anywhere? I ask that because to do that the flasher must be changed and that sometimes affects the cruise.
Could someone follow you to see if the brake lights flicker momentarily while you're driving? If the brake light switch is too close to the pedal it could make momentary contact.
 

·
Registered
Joined
·
1,251 Posts
Hi
Have issue with cruise control not engaging. Have checked with Tech2 and switches seem to work ok, only issue I can see is that the “Stop lamp pedal applied”. Now the pedal switch is working fine as when applied the brake lights come on. Is there a second switch for cruise control?
When you checked it with the tech2 and saw that the stop lamp pedal applied message. This is your clue as to what is wrong with your cruise control. The brake pedal switch has several sections to it, not just brake lights. So if the computer sees this message, it will not allow the cruise to engage. You need a new brake light switch to fix it. Older brake light switches had only two wires going to them, the one in the R and most modern vehicles have many wires going to them for brake lights, cruise control, ABS and a few other things.
 

·
Premium Member
Joined
·
2,889 Posts
Hi
Have issue with cruise control not engaging. Have checked with Tech2 and switches seem to work ok, only issue I can see is that the “Stop lamp pedal applied”. Now the pedal switch is working fine as when applied the brake lights come on. Is there a second switch for cruise control?
Its great that you have a tech 2 and provided us with this screen shot.
I agree with @06 Blue SSR -- brake light switches are no longer an on and off two terminal switch.

Because you have a tech 2 -- did you check all modules for codes ?-- in particular the EBCM
Just because the check engine light is not on does not mean you will not find a code!!!

This switch has one part of the switch (for the lights) that is open with foot off pedal and closed when you depress the pedal and an other part of the switch is closed (applied) at rest and opens when you depress the brake pedal.

Picture #1 shows the normally closed TCC brake and cruise control RELEASE switch sends signals to EBCM (electronic brake control module) and the PCM ( powertrain control module).

Reading step 8 of the the cruise control always inoperable diagnostic chart (picture 2)shows with your foot on the pedal the scan tool should display "Stop lamp pedal applied" -- which also means it should read unapplied or similar with your foot off pedal.

Before you jump out and a order a new switch -- if you want to know if a switch will fix the problem try this.

First unplug the switch on the brake pedal watch the scan tool-- does the display change from applied or something similar then jumper the purple wire to the pink wire the scan tool should then show a change in what is displayed.

NO - you have a wiring problem
Yes -- a new switch will most likely fix your problem --

Let me know if you require the other diagnostic charts --
Found in service manual under cruise control -- diagnosis by symptom
 

Attachments

·
SSR Overseas, Ireland,
Joined
·
387 Posts
Discussion Starter #8
Thanks for the advice, much appreciated.

I will get a closer look at the brake switch tomorrow as I had discounted this due to the brake lights working ok when pedal was pressed. The rear lights have been modified by previous owner as we need Amber turn signals and not a flashing brake lights over here, so that may have compounded the issue too.

To be honest I got the Tech 2 before Christmas, and only recently got the correct software, and am only getting the hang of the tool. There is a bunch of screens and abbreviation that I don't understand yet. On a bit of a learning curve ?

I will keep you posted as to my progress with issue.

Thanks again for your comments & help

Richard
Ireland SSR
 

·
Registered
Joined
·
190 Posts
As mentioned earlier, if the PO has switched over to LED stoplights, then that could also be the cause- it was for one of my cars. The LED's store enough energy when lit, that they act as a capacitor when the brake pedal is released, putting a small amount of voltage back into the line. That voltage is enough for the Cruise control ECU to believe that the brakes are still applied. You can test this by re-installing just one regular brake lamp. If the problem goes away, then you've found the culprit. There are several solutions on the net to fix this- I used the one using a relay to switch the power line of the brake lights to ground when power is removed- thus depleting the capacitor charge in the LED's.
 

·
SSR Overseas, Ireland,
Joined
·
387 Posts
Discussion Starter #10 (Edited)
I have the message of
Stoplamp pedal switch Applied constantly on.
I tried unplugging the brake pedal switch and got still got same stop lamp message of applied.
I also got new message of “ cruise release brake pedal “applied”.

I then tried shorting our purple & pink on the wiring harness plug from pedal switch and got and this changed the message of “ applied / released” on the cruise release brake pedal .

This did not change message on the stop lamp pedal switch “applied”
 

Attachments

·
One of the SoCal Nuts
Joined
·
28,400 Posts
I have the message of
Stoplamp pedal switch Applied constantly on.
I tried unplugging the brake pedal switch and got still got same stop lamp message of applied.
I also got new message of “ cruise release brake pedal “applied”.

I then tried shorting our purple & pink on the wiring harness plug from pedal switch and got and this changed the message of “ applied / released” on the cruise release brake pedal .

This did not change message on the stop lamp pedal switch “applied”
I think you have cleared the brake light switch of being the culprit and need to move to the suggestion from darbysan regarding installation of one conventional brake lamp.
 
  • Like
Reactions: Autoprof

·
Premium Member
Joined
·
2,889 Posts
I agree with @BlueStreak --
Your switch is not the issue
Unplugged the stop light switch should show released -- switch should be open so unplugged simulates an open switch -- this circuit is not working right!

The TCC/cruise switch should show applied with it unplugged and released with wires jumped --- This circuit is working right.


You did mention that your rear lights had been modified by previous owner.
You never mentioned if you had LEDs, Do you have LEDs in the rear?

Has the cruise control ever worked? -- you might be onto to something regarding the modified wiring.

When checking brake light functions _ I assume when you said all was good, it meant all came on BRIGHT and remembered to check high mount light in tailgate.

Do turn signals flash at correct speed and intensity? - a dim bulb could be a sign of a bad connection (power or ground)

If all lights do in fact work normally AND they are not LEDs -- try removing fuse #34 (STOP) in rear fuse box. Now note scanner display for the stoplight switch with it plugged in!(the switch not the fuse). NOTE Stop lights should still function - be aware this might set a trouble code in the PCM.

Explanation -- the stoplight switch not only supplies power to operate lights, the same part of the switch sends a signal to the throttle control actuator module (TAC). The TAC is what actually controls the speed (cruise control). This signal is also communicated to the PCM though the UART serial data line - this is how you can read it on the scan tool

When you look at diagram #1 attached you can see the stoplight switch near the top of my red line. Following the red line down you see a path that goes to a block labeled "exterior lighting schematics". This is picture #2. This shows how the flasher module receives power to operate the rear lights. (The center high mounted stop light (CHMSL) gets power from same wire but inside the rear fuse box BEFORE fuse #34). Continuing down red line you find fuse in the #34 rear fuse box and then fining the signal terminates into the TAC (bottom of my red line). So removing fuse #34 will remove the signal from the TAC and the scanner this should then show stop lamp switch released (or similar).
It may set a code if you press on brake pedal because PCM will see TCC/cruise switch change and the stop switch did not change. So it knows something is wrong - but won't know what!
 

Attachments

·
SSR Overseas, Ireland,
Joined
·
387 Posts
Discussion Starter #13
Thanks guys for information.
Will have to examine further.
My rear lights have been modified see attached pictures, I still have traditional filament bulb for rear parking / break light which do not flash on turn signal. Cleverly inside the rear lamp fitting they installed a pcb with amber leds. These flash on turn signal.

I need to get at fuse #34 in rear box. Is this the box in behind passenger seat in the waterfall ?

Richard
 

Attachments

·
Premium Member
Joined
·
2,889 Posts
Thanks guys for information.
Will have to examine further.
My rear lights have been modified see attached pictures, I still have traditional filament bulb for rear parking / break light which do not flash on turn signal. Cleverly inside the rear lamp fitting they installed a pcb with amber leds. These flash on turn signal.

I need to get at fuse #34 in rear box. Is this the box in behind passenger seat in the waterfall ?

Richard
OK thanks for update BUT did the cruise control ever work after lights were modified - or since you had the SSR? Meaning is this a new problem or an on going one?

I see the tail light is a normal bulb and the T/S is LED board but what is this other light I circled - is this what they are using for a brake light?

Yes fuse #34 in the rear fuse box is the one behind the passenger seat behind the access panel on the side of the waterfall.

IMPORTANT be sure to remove cup holder from console before moving seat forward to gain access.
 

Attachments

·
SSR Overseas, Ireland,
Joined
·
387 Posts
Discussion Starter #17 (Edited)
Yes the cruise control did work when I got it.

Autoprof, Very well spotted. ��
This little bulb is the rear parking light that illuminates the rear lamp at the same time as the side markers are illuminated.

In first post I have a picture from Tech 2, what is the difference between
A. Stop lamp Pedal switch Applied
B. Cruise release brake pedal released

the “ cruise release brake pedal “changes from applied to release when I press the break pedal and also when I shorted out the pink & purple wires.
The stop lamp pedal seems stuck ( on ) applied


What do the other wires in the pedal switch do ?
 

·
Premium Member
Joined
·
2,889 Posts
The display on tech 2

The cruise control release is the a part of the brake switch for the torque connvertor clutch (TCC and cruise control release. This switch is closed when your foot is off the pedal and it opens when you depress the pedal - the computer is seeing this change properly it is connectors D and C on the switch

I include the connector wiring diagram to help

The stop light switch should be open with your foot off the pedal (0 volts) and closed (close to 12 volts) when you depress the pedal. The computer is constantly seeing voltage on this line and thinks the pedal is depressed all the time. It is connectors A and B on the switch (the two white wire are both A) these are the outputs from the switch and One white wire goes to the flasher module and the other white wire goes to the rear fuse box - where it splits to the two fuses -- one fuse for the CHMSL and the other fuse for the signal to the TAC.

The remaining two wires on the brake switch are for the park interlock circuit of your shifter - used as an input to only allow you to move shifter from the park position if you have your foot on the brake.


So the picture with the light on is the brake light -- because the small bulb I circled does not appear to be on!

I wonder how they wired this set-up and if they used any type of diodes to convert the flashing signals to solid or ignore solid -- I know that when connecting a trailer to a car with a separate turn signal and brake light it requires an adapter which contains some diodes. I have never thought about converting a harness the other way? I wonder if any kind of module was spliced into to harness near rear lights.

I think that this might be where your problem lies. I could not predict or diagnosis it very easily without a diagram or the opportunity to trace the wiring myself.

Let me know what happens when fuse is pulled and see if there is any information on lighting system conversion.
 

Attachments

·
SSR Overseas, Ireland,
Joined
·
387 Posts
Discussion Starter #19
I now have working cruise control. Can set speed, increase speed, decrease speed, touch brake and instantly disengages. Great.

Only issue is the indicator light in dash does not illuminate when cruise control is active.

The root cause was fuse 34 in rear compartment was missing !

Thanks again to all who helped me here especially Autoprof with the wiring diagrams.
 

·
Premium Member
Joined
·
2,889 Posts
Great job.
Glad to help.

This is strange, what happened to fuse?
I assume display on tech 2 now changes when pedal is depressed.

I can't see my indicator for cruise, not bright enough.
 
1 - 20 of 23 Posts
Top