Ford cruise control problems


  #1  
Old 04-06-14, 11:25 AM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
Ford cruise control problems

OK, so the next nemesis I'd like to figure out is why my cruise control quit working years ago. It used to work... then started working intermittently, then quit altogether, never to work again.

Its on a 2002 Ford F150 4.2L w/manual transmission.

I've gone through the on board diagnostic test, and at the conclusion of that test, the dashboard cruise light blinks once to indicate the test was completed sucessfully. (no errors) However there must be a problem that it's not detecting for some reason.

So I've gone on to test the voltage at the cruise servo.

Pin 9 shows 12V (as it should)
Pin 7 shows 12V (as it should)
Pin 5 shows 7.9V (as it should) at KOEO
Pin 5 shows 12V (as it should) when pushing the cruise ON button
Pin 5 shows 0V (as it should) when pushing the cruise OFF button
Pin 5 shows 3.5 V (as it should) when pushing the SET/ACCEL button
Pin 5 shows .9 V (don't have the spec) when pushing the COAST button

Now here is the problem.

Pin 4 shows 12V when stepping on the brake pedal (as it should)
Pin 4 shows 12V when NOT stepping on the brake pedal. (Bad! should read 0V!)

I replaced the BOO (or BPP) switch and no change. There is a little clutch pedal toggle switch actually on the pedal and it also works... but I'm not sure about the clutch pedal position switch. It has 6 pins that perform 3 functions and I wonder if all of them are working correctly.

I'm probably going to try jumpering the CPP switch and see where that gets me.
 
  #2  
Old 04-06-14, 04:54 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,837
Received 1,475 Votes on 1,363 Posts
Make sure the ground wire(black/pink) to the brake switch is grounded.

The red line I drew shows the normal path from ground to pin 4 with both pedals at normal. Since you are showing pin 4 at high.... you've lost the ground or the connection thru the switches to ground.

Name:  cc.jpg
Views: 1470
Size:  35.2 KB
 
  #3  
Old 04-06-14, 08:34 PM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
Well, I have to be brutally honest with myself and admit that this is one battle that I am probably not going to win.

Number one, electrical things baffle me. I barely understand the most basic concepts of electrical, and don't really know very well which setting to put the multimeter on. Volts I get... but the ohms baffles me. There seems to be 5 or 6 settings for ohms.

Number two, and this is probably the biggest one, is that I'm color blind. So all these stupid color descriptions for wires might as well be in another language because they mean absolutely nothing to me. Unless it's a solid black wire or a white wire or a yellow wire, I have a snowball's chance in hell of figuring out what wire is what, especially when they are dirty. The small amount of color on those little stripes just does not stand out at all, and there's probably a 90% chance I would get it wrong even if I tried.

So while I would love to fake it and figure this out, I just have no way of figuring out which wire is the pink / black one at the BPP switch, and truthfully I don't think there is one. Maybe it's just harder to see in the dark. I will try again tomorrow after work.

The third thing that is confusing me is that my diagram shows 2 wires (LT GRN/RED) power to BPP switch, and (LT GRN) power from the BPP switch. Your diagram shows 3 wires at the BPP switch, and different colors. (confusing!) On top of that, when I get under the steering wheel, there are 5 wires at the BPP switch harness. (ready to give up by now)

So I take the 12V test light, connect one end to a good ground and back probe the connections. I will number the pins 1 through 5 so as to keep colors out of the picture. Pin 1 12V. Pin 2 0V. Pin 3 12V. Pin 4 12V when brake is applied. Pin 5 0V.

So I make the assumption that the pins with 0V are grounds. I test for ohms from those pins to a good ground and I come up with infinite resistance, which tells me that either none of those wires are grounded, or that my assumption was wrong. So I really have no idea what I'm doing by now.

All the brake lights work, none are burnt out. I am just really baffled by what to do next. What you say makes sense, I understand that Pin 4 is not reading 0V when the brake is being applied... I'm just not able to figure out the next move, I think mainly because of the color blind thing. That and I feel like an electrical idiot!
 
  #4  
Old 04-06-14, 09:28 PM
N
Member
Join Date: Aug 2006
Location: santa fe /texas
Posts: 997
Received 0 Votes on 0 Posts
just curious,
have you tested/ replaced the pressure switch on the ft. of the Master Cyl ?
 
  #5  
Old 04-06-14, 09:55 PM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
Thanks, newtofta, but this truck doesn't have the pressure switch. I know, it's odd. Best I can figure, someone replaced the master cylinder with one that doesn't have the pressure switch on the front (used a master cylinder that was for an F150 w/no cruise) and they even removed the 2 pin harness it connected to. I don't "think" the way they wired it is the problem however, as it has always been that way since I have owned it and the cruise USED to work.

At any rate, I did clear up one confusing thing. The diagram that I have, and the diagram that PJmax posted, don't match my BPP Switch.

But I finally figured out what words to Google and found this illustration that more closely resembles it, so maybe I can make some headway with that, although I don't know if the wire colors it shows are accurate, but having the pin numbers is very helpful, so I should be able to figure something out.



Apparently I numbered them backwards in my post, above. I will have to test them again to make sure. From the looks of it, 1 is the ground, and 2-5 should all be hot when the brake pedal is pushed.
 
  #6  
Old 04-07-14, 03:28 PM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
I'm probably going to try jumpering the CPP switch and see where that gets me.
WOOHOO!!!

Hot dang I think I figured it out! I thought I had narrowed it down to the CPP switch (6 terminal connector)... so I unplugged it and tested for 12V while operating the brake. It seemed like terminal 4 reacted to the brake pedal, so I guessed that it was the correct one to jumper. I made a paperclip jumper between 3 and 4 and when I looked up over the dashboard at my voltmeter (which was connected to the cruise servo pins 4 & 10) it finally said 0V!!! Yay!!!

I ran through the on-board cruise diagnostic again, pushing the steering wheel buttons in the right order, and this time the cruise servo actually moved the throttle at the end of the test! WOOHOO!!!

So I am guessing that means the problem is within the CPP switch.

But I think there must be some other problem too... because as I was testing the brake pedal and watching the voltmeter showing the voltage go from 10V to 0V across cruise servo pins 4 & 10.... every once in a while it would seem to stick at 10V again. But if I popped the brake pedal, it would go back down to 0V. Come to find out, I have to lift the brake pedal slightly with my foot to get it to go to ground. Not really sure what that means? My brake switch is new, so... ???

I'll be picking up a new clutch position switch tomorrow and see if that doesn't fix the problem. It better! I'd like to have my cruise back again!
 
  #7  
Old 04-07-14, 05:53 PM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
Ok, so I couldn't wait. One paper clip and 3 little u-shaped jumpers later, I was cruising along the highway with my cool new cruise control working again! Yesssssssssssssssss!



Also found that the CPP switch I need is only $24 on Amazon.
 
  #8  
Old 04-07-14, 06:25 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,837
Received 1,475 Votes on 1,363 Posts
AWESOME.... I was thinking about this all day and how to help you around the wire colors and you figured it out on your own. You applied logic and figured out the problem.

TWO and a
 
  #9  
Old 04-07-14, 07:42 PM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
LOL, thanks PJmax! It feels great to have fixed it. I've always liked puzzles, so all this auto repair has been right up my alley. Now I will have nothing to keep me awake at night as I stare at the ceiling!

Maybe now you can teach me how to use the multimeter. I've got the Klein mm100.



Let's say I want to test my 12V car battery. (fried my last cheap-o multimeter that way... LOL) If I'm testing the amperage, I should put the red lead on the left side (10A) and turn the dial to 10A? And if I'm testing the voltage, does it matter which side the red lead is attached to? I guess I just don't want to burn this one up.

I also don't really understand which setting I should have it on when testing resistance. I think for most of the work I did on the truck, 12V stuff, I had it set on 20K. Such as when you would want to test between two cruise servo pins, and the expected result should be 5 ohms or less... what would you normally set it on?
 
  #10  
Old 04-07-14, 09:10 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,837
Received 1,475 Votes on 1,363 Posts
The ONLY time you put the meter in amperage is if you have the meter in series with the load.
200u-20m-200m-10A are all current scales. The 10A scale is only active when the red probe is in the 10A red port. Applying a voltage to the meter when in one of the A positions will blow a fuse and the meter will stop working.

V~ Stands for AC voltages - you have >200v and >600v

V= Stands for DC voltages - you have >200mv and >2v and >20v and >200v and >600v
So for most auto work you'd use the 20V position.

Ohms - you have 2M - 200k - 20k - 2k - 200 - 200 w/audible

For testing basic continuity you would use the 200 scale. The 200 w/audible scale is cool for when you can't see the meter but want to check continuity. The 200 scale would be used when you were expecting a resistance under that..... like 5 ohms.

The higher the number the more sensitive the meter is. The M stands for million ohms and the k stands for 1000. If you wanted to check something for leakage.... like maybe an electric motor..... you'd use the 2M setting and check from each power wire to the metal frame. You should see nothing. If you do it's leakage and indicated a problem. You could also use this with the magnetos and devices like that aren't internally grounded. In this scale the meter is so sensitive it will read your skin resistance.

This is a digital meter but not autoranging. That means when checking an unknown voltage.... always choose the highest voltage setting and work your way down.
 
  #11  
Old 04-26-14, 05:27 AM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
OK, so I want to test the amperage that a 12V fuel pump is drawing. I am suspecting that it's just humming and not actually pumping. You are saying that I would put the multimeter on 10A... and put it in series with the circuit, meaning I would use the black and the red probes to close the circuit to the fuel pump, running the voltage through the multimeter?
 
  #12  
Old 04-26-14, 10:19 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,837
Received 1,475 Votes on 1,363 Posts
Yes.... you have it exactly right.
If the device you are testing draws over 10A the safety fuse inside the meter will open.
 
  #13  
Old 04-26-14, 04:24 PM
XSleeper's Avatar
Group Moderator
Thread Starter
Join Date: Dec 2004
Location: USA
Posts: 27,042
Received 899 Votes on 825 Posts
Thanks, the fuel pump was bad.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: