Cruise Control Woes
10-09-07, 01:40 PM
#1
Jpk3200
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Cruise Control Woes
The car: 1990 Turbo II
The problem: After pressing the Main switch on the cruise lever, the MAIN light does not come on.
Things I have checked:
1. Meter and Stop fuses
2. Took the switch out and tested all functions and they all work - even MAIN and CRUISE lights
3. After turning ignition to ON, I have battery voltage on the B/Y wire on the plug of the cruise switch
4. I have battery voltage on the G/Y wire on the Cruise Control Unit plug as long as I hold down the MAIN switch on the cruise lever
I am not getting any promising results that require the step of having the Main swith ON (on page T-76 of FSM)
My cruise control used to work perfectly about a year ago, and I didn't get around to fixing it until now. At that time, I could still get the MAIN light to light up. I ran error codes according to the FSM and got Error Code 01. Sometime around May, the MAIN light would no longer light up, but as stated before, I know the bulb is good.
When I turn on my lights at night, the letters on the switch light up.
Could there be a bad harness somewhere, or something obvious that I missed? I'm trying to figure out what happend between a system that turned on (but not CRUISE) to a system that doesn't indicate life at all.
The problem: After pressing the Main switch on the cruise lever, the MAIN light does not come on.
Things I have checked:
1. Meter and Stop fuses
2. Took the switch out and tested all functions and they all work - even MAIN and CRUISE lights
3. After turning ignition to ON, I have battery voltage on the B/Y wire on the plug of the cruise switch
4. I have battery voltage on the G/Y wire on the Cruise Control Unit plug as long as I hold down the MAIN switch on the cruise lever
I am not getting any promising results that require the step of having the Main swith ON (on page T-76 of FSM)
My cruise control used to work perfectly about a year ago, and I didn't get around to fixing it until now. At that time, I could still get the MAIN light to light up. I ran error codes according to the FSM and got Error Code 01. Sometime around May, the MAIN light would no longer light up, but as stated before, I know the bulb is good.
When I turn on my lights at night, the letters on the switch light up.
Could there be a bad harness somewhere, or something obvious that I missed? I'm trying to figure out what happend between a system that turned on (but not CRUISE) to a system that doesn't indicate life at all.
10-09-07, 04:18 PM
#2
HAILERS
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Look at page T-70 of the free online FSM for series five.
It seems to me what you shouild do, is get a meter out. Pull the plug off the cruise switch. Put one meter lead on the PIN where the black/yellow wire(power wire) goes. Then look at that schematic on that page T-70. See the OTHER black/yellow wire??? Put the meters other lead on that PIN on the cruise switch.
Meter to ohms. Press the MAIN switch. You should get continuity on the meter as the switch is put to ON.
That at least tells you the switch works. BUT I notice there's a better way. Leave the plug on the cruise switch. PUll the plug off the cruise control unit. Put the meters neg lead on a good gnd point. Put the positive lead on the G/Y wire on the control units plug. Key to ON. Meter to dcvolts. The meter should read batt voltage as the switch is held or pressed to ON. It should stay there when the switch button is released. Does that happen?????
If you get batt voltage when the button is pressed and released, then there must be a problem either inside the cruise unit or the wire from the cruise unit to the light in the switch that is for the MAIN light (LB wire on the curise plug).
It seems to me what you shouild do, is get a meter out. Pull the plug off the cruise switch. Put one meter lead on the PIN where the black/yellow wire(power wire) goes. Then look at that schematic on that page T-70. See the OTHER black/yellow wire??? Put the meters other lead on that PIN on the cruise switch.
Meter to ohms. Press the MAIN switch. You should get continuity on the meter as the switch is put to ON.
That at least tells you the switch works. BUT I notice there's a better way. Leave the plug on the cruise switch. PUll the plug off the cruise control unit. Put the meters neg lead on a good gnd point. Put the positive lead on the G/Y wire on the control units plug. Key to ON. Meter to dcvolts. The meter should read batt voltage as the switch is held or pressed to ON. It should stay there when the switch button is released. Does that happen?????
If you get batt voltage when the button is pressed and released, then there must be a problem either inside the cruise unit or the wire from the cruise unit to the light in the switch that is for the MAIN light (LB wire on the curise plug).
10-09-07, 09:57 PM
#3
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oOOPS. I went back and read all what you wrote. You already did those things.
Question: When you press the MAIN button and then let go, does the batt voltage remain on the G/Y wire at the control unit?
Can you pull the plug off the cruise switch, and then on the switch itself, ohm out b/t where the pin for the LB wire would attach and where the pure black wire would attach? It should ohm out thru the light bulb for the MAIN.
Or how about this. There are two things that can turn the cruise off. One is the brake switch being depressed and the other the clutch switch being depressed.
Put the meter on a good gnd point and the positive meter lead to the Green wire in the cruise unit. Key ON and push on the brake pedal. Batt voltage should NOT be there til you press the pedal. Same with the clutch wire, the Y/L wire. No voltage til you press the pedal.
Have you ever tried to drive at a steady pace and HOLD the MAIN button down while trying to engage the cruise????? Try that for grins.
You might ohm out both black wires at the switch and the cruise control unit plug to see if they ohm out to gnd.
You say this cruise worked at one time so I won't ask if you have n/a and turbo parts mixed up or series four /five parts mixed up.
If you pull the plug off the cruise control unit, and put a meter on ohms and one lead to the GO wire and other meter lead to a known gnd, do you get a ohms reading when the switch is put to SET? Should.
You have 12vdc on the B/Y wire on the cruise control unit, also?
Sorry 'bout my first post.
Question: When you press the MAIN button and then let go, does the batt voltage remain on the G/Y wire at the control unit?
Can you pull the plug off the cruise switch, and then on the switch itself, ohm out b/t where the pin for the LB wire would attach and where the pure black wire would attach? It should ohm out thru the light bulb for the MAIN.
Or how about this. There are two things that can turn the cruise off. One is the brake switch being depressed and the other the clutch switch being depressed.
Put the meter on a good gnd point and the positive meter lead to the Green wire in the cruise unit. Key ON and push on the brake pedal. Batt voltage should NOT be there til you press the pedal. Same with the clutch wire, the Y/L wire. No voltage til you press the pedal.
Have you ever tried to drive at a steady pace and HOLD the MAIN button down while trying to engage the cruise????? Try that for grins.
You might ohm out both black wires at the switch and the cruise control unit plug to see if they ohm out to gnd.
You say this cruise worked at one time so I won't ask if you have n/a and turbo parts mixed up or series four /five parts mixed up.
If you pull the plug off the cruise control unit, and put a meter on ohms and one lead to the GO wire and other meter lead to a known gnd, do you get a ohms reading when the switch is put to SET? Should.
You have 12vdc on the B/Y wire on the cruise control unit, also?
Sorry 'bout my first post.
Last edited by HAILERS; 10-09-07 at 10:06 PM.
10-10-07, 12:54 PM
#4
Jpk3200
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Question: When you press the MAIN button and then let go, does the batt voltage remain on the G/Y wire at the control unit?
Or how about this. There are two things that can turn the cruise off. One is the brake switch being depressed and the other the clutch switch being depressed.
Put the meter on a good gnd point and the positive meter lead to the Green wire in the cruise unit. Key ON and push on the brake pedal. Batt voltage should NOT be there til you press the pedal. Same with the clutch wire, the Y/L wire. No voltage til you press the pedal.
Put the meter on a good gnd point and the positive meter lead to the Green wire in the cruise unit. Key ON and push on the brake pedal. Batt voltage should NOT be there til you press the pedal. Same with the clutch wire, the Y/L wire. No voltage til you press the pedal.
a) defective wiring or ground
b) defective actuator
c) defective stoplight switch (for cruise)
Perhaps that my Stop Switch 2 (the smaller connection on the Stop Switch unit) has gone bad and is keeping the system from turning on? I pulled the switch and tested both Stop Switches 1 and 2. I knew Stop Switch 1 worked since my brake lights work. I got the described continuity in the FSM. For Stop Switch 2, I got something close to continuity. It kind of bounces around 1 to 5 ohms. Enough to screw things up? I did the same for the clutch switch, and it tested good.
I am not getting any good results from procedures that require the Main switch to be ON.
Have you ever tried to drive at a steady pace and HOLD the MAIN button down while trying to engage the cruise????? Try that for grins.
You might ohm out both black wires at the switch and the cruise control unit plug to see if they ohm out to gnd.
If you pull the plug off the cruise control unit, and put a meter on ohms and one lead to the GO wire and other meter lead to a known gnd, do you get a ohms reading when the switch is put to SET? Should.
You have 12vdc on the B/Y wire on the cruise control unit, also?
10-10-07, 02:26 PM
#5
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I've series four cars and have messed with a series five switch in the past....but memory fades on how the Main worked. It's out in the shed somewhere. I'm really not sure if its a momentary switch or one you push and it's ON and push again and it's OFF. So don't pay too much attention to what I said about that switch.
I'd check the two gnds just to make sure. No lights etc are going to work without the gnd on both switch and CCU.
Also I suppose I'm going to have to stare at the series five CCU schematic again. I don't remember two stop switches. The stop and cruise only play a part IF they are putting out 12vdc to the CCU. So if the key is ON and there is no input to those two wires at the CCU plug, then that isn't the problem.
I'll look a little harder at the diagrams and maybe come up with a fresh idea. Actuator plug on? Of course it is.
I'd check the two gnds just to make sure. No lights etc are going to work without the gnd on both switch and CCU.
Also I suppose I'm going to have to stare at the series five CCU schematic again. I don't remember two stop switches. The stop and cruise only play a part IF they are putting out 12vdc to the CCU. So if the key is ON and there is no input to those two wires at the CCU plug, then that isn't the problem.
I'll look a little harder at the diagrams and maybe come up with a fresh idea. Actuator plug on? Of course it is.
10-10-07, 04:01 PM
#6
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*****I have battery voltage on the G/Y wire on the Cruise Control Unit plug as long as I hold down the MAIN switch on the cruise lever
************************************************** ***************
?
And I now see the second stop switch. That's different than series four. That might be something for me to find out about.
Have you ever taken the switch by itself, and gotten on the pins for the G/L, L/R and L/W with one lead of the meter and the other lead on the pin that is gnd (B), and then flip the Set, Coast, Resume to see if there is continuity b/t the gnd pin and those three wires as you press the appropriate switch? That's how those three settings work. By putting a gnd signal on thsoe wires momentarily to get them to work. Might find something there.
On a BAD series four switch that I had, the problem was the SET switch. When pulled the switch did not put a gnd on the G/L wire. The problem was a bad contact inside the switch handle.
************************************************** ***************
?
And I now see the second stop switch. That's different than series four. That might be something for me to find out about.
Have you ever taken the switch by itself, and gotten on the pins for the G/L, L/R and L/W with one lead of the meter and the other lead on the pin that is gnd (B), and then flip the Set, Coast, Resume to see if there is continuity b/t the gnd pin and those three wires as you press the appropriate switch? That's how those three settings work. By putting a gnd signal on thsoe wires momentarily to get them to work. Might find something there.
On a BAD series four switch that I had, the problem was the SET switch. When pulled the switch did not put a gnd on the G/L wire. The problem was a bad contact inside the switch handle.
10-10-07, 04:09 PM
#7
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****I have battery voltage on the G/Y wire on the Cruise Control Unit plug as long as I hold down the MAIN switch on the cruise lever*********
It would be interesting if you had all the plugs connected and with the meter backprobed the L/B wire in the CCU plug to see if there is an output there when the Main switch is held.
And do you have batt voltage on the B/Y wire on the CCU unit? with the key ON? I know you have it at the switch.
It would be interesting if you had all the plugs connected and with the meter backprobed the L/B wire in the CCU plug to see if there is an output there when the Main switch is held.
And do you have batt voltage on the B/Y wire on the CCU unit? with the key ON? I know you have it at the switch.
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10-13-07, 12:41 AM
#8
Jpk3200
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Alright, I finally got a chance to check some more stuff out:
Both grounds are good from both harnesses (measuring the resistance from the B wire from both to ground are zero)
These are all good. The only button that didn't ohm out was the Main switch. That's because according to the wiring diagram, it isn't supposed to.
Yep. It's connected.
Yes.
And as stated before, I have battery voltage across G/Y wires as long as I hold the Main switch down.
Not sure what you mean here. Do you mean while it's connected to the Cruise Control Unit, I measure the output from the opposite side of the harness?
I still can't figure out why I can't get the CRUISE indicator to light up from the procedure shown on page T-76 for terminal f. Maybe I'm doing something wrong? I have one probe on ground, and the other connected to terminal f on the CC unit. This is supposed to make the CRUISE light come on? I get 12VDC when I do this, but pressing any/all the switches on the cruise switch doesn't make the light come on.
Bad CC computer? I took it apart a few weeks ago and made sure all the connections were good - they were.
I'd check the two gnds just to make sure. No lights etc are going to work without the gnd on both switch and CCU.
Have you ever taken the switch by itself, and gotten on the pins for the G/L, L/R and L/W with one lead of the meter and the other lead on the pin that is gnd (B), and then flip the Set, Coast, Resume to see if there is continuity b/t the gnd pin and those three wires as you press the appropriate switch?
Actuator plug on? Of course it is.
And do you have batt voltage on the B/Y wire on the CCU unit? with the key ON?
And as stated before, I have battery voltage across G/Y wires as long as I hold the Main switch down.
It would be interesting if you had all the plugs connected and with the meter backprobed the L/B wire in the CCU plug to see if there is an output there when the Main switch is held.
I still can't figure out why I can't get the CRUISE indicator to light up from the procedure shown on page T-76 for terminal f. Maybe I'm doing something wrong? I have one probe on ground, and the other connected to terminal f on the CC unit. This is supposed to make the CRUISE light come on? I get 12VDC when I do this, but pressing any/all the switches on the cruise switch doesn't make the light come on.
Bad CC computer? I took it apart a few weeks ago and made sure all the connections were good - they were.
10-13-07, 03:37 PM
#9
Jpk3200
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Actually, I was thinking about this at work today...
Would a bad actuator keep the light from coming on? I mean I did get Error Code 01 (back when the light turned on), which could be a defective actuator. As the previous post said, the grounds for the CC unit and switch were good, so it could only mean a bad stop switch (for cruise) or defective actuator right? And... I said that the stop switch (for cruise) tested pretty good (only like 1-3 ohms).
All I've done is verify that the actuator plug is in. I haven't done the procedures outlined on page T-77. The connection to the actuator seems like a beast to get to and test, which is why I haven't done it yet (for fear that I forget how things are put back).
Any tips for getting to that plug on the actuator more easily? I'd like to be able to remove as much as possible.
Would a bad actuator keep the light from coming on? I mean I did get Error Code 01 (back when the light turned on), which could be a defective actuator. As the previous post said, the grounds for the CC unit and switch were good, so it could only mean a bad stop switch (for cruise) or defective actuator right? And... I said that the stop switch (for cruise) tested pretty good (only like 1-3 ohms).
All I've done is verify that the actuator plug is in. I haven't done the procedures outlined on page T-77. The connection to the actuator seems like a beast to get to and test, which is why I haven't done it yet (for fear that I forget how things are put back).
Any tips for getting to that plug on the actuator more easily? I'd like to be able to remove as much as possible.
10-13-07, 10:42 PM
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Jpk3200
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Alright, I figured out that the connector is long enough to test it without taking stuff out. It was probably the most difficult plug that I've ever taken off.
I got about 8-9 ohms between terminals A and C. Also, the Pull, Stop, Extend, and Release all work properly.
I'm keeping that **** unplugged for now, just in case I need to check something else there.
I got about 8-9 ohms between terminals A and C. Also, the Pull, Stop, Extend, and Release all work properly.
I'm keeping that **** unplugged for now, just in case I need to check something else there.
10-14-07, 05:30 AM
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********Not sure what you mean here. Do you mean while it's connected to the Cruise Control Unit, I measure the output from the opposite side of the harness?
************************************************** **********
I'm writing this from memory since I've no schematic with me now........The power to light up the Main bulb comes from the CCU on the LB wire once the CCU is powered up. So I was suggesting that if every plug is connected up, and the LB wire is probed with a meter as the Main switch is depressed, it would be interesting to know if the LB has power on it coming from the CCU.
I was suggesting checking out the Resume, Set and Coast because I assume if the COAST switch had a gnd on it all the time, then the cruise control won't work/engage.
Will the light come on if the actuator is bad? I'll check that in the next day or so. I don't know for sure.
Question: Are all the parts to the cruise the same parts NOW as to when the cruise worked before?
************************************************** **********
I'm writing this from memory since I've no schematic with me now........The power to light up the Main bulb comes from the CCU on the LB wire once the CCU is powered up. So I was suggesting that if every plug is connected up, and the LB wire is probed with a meter as the Main switch is depressed, it would be interesting to know if the LB has power on it coming from the CCU.
I was suggesting checking out the Resume, Set and Coast because I assume if the COAST switch had a gnd on it all the time, then the cruise control won't work/engage.
Will the light come on if the actuator is bad? I'll check that in the next day or so. I don't know for sure.
Question: Are all the parts to the cruise the same parts NOW as to when the cruise worked before?
01-11-08, 02:34 PM
#13
Jpk3200
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Just wanted to bring some closure to this topic in case people have the same problems as I had.
When I first tested the cruise switch via the FSM, everything on the switch worked. Then the Main switch failed, and I ended up getting a new cruise switch.
The error codes that I had mentioned were a result of failed circuitry inside the unit and did not have anything to do with a faulty harness/ground/brake switch/actuator. This was one of the reasons that I was initially led to believe that the unit was still OK since it did not give a FAULTY UNIT code.
I tested the switch, grounds, harness, and actuator.
It turns out that the cruise brain had died on me. Thanks to viperkiller7, I got a new unit and everything works again. I probably should have just replaced the unit in the first place when it first showed no signs of life but oh well. I wanted to make sure that it wasn't something in the switch/harness.
Many thanks to HAILERS for helping me pinpoint the problem.
+1000 forum cookies to both of you
When I first tested the cruise switch via the FSM, everything on the switch worked. Then the Main switch failed, and I ended up getting a new cruise switch.
The error codes that I had mentioned were a result of failed circuitry inside the unit and did not have anything to do with a faulty harness/ground/brake switch/actuator. This was one of the reasons that I was initially led to believe that the unit was still OK since it did not give a FAULTY UNIT code.
I tested the switch, grounds, harness, and actuator.
It turns out that the cruise brain had died on me. Thanks to viperkiller7, I got a new unit and everything works again. I probably should have just replaced the unit in the first place when it first showed no signs of life but oh well. I wanted to make sure that it wasn't something in the switch/harness.
Many thanks to HAILERS for helping me pinpoint the problem.
+1000 forum cookies to both of you
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