Ranger V8 factory cruise/speed control not working

[Rangstang]

Hi guys,

I posted this in electrical last Tuesday, but haven't had a single response, so I'm hoping it's the V8 aspect that's causing that...

I installed a 99 Mountaineer 5.0 in my 2000 Ranger Trailhead Group 2WD with a Mustang T5 back in 2010 with a lot of your help (thanks). My truck is an XL and didn't come with speed control. I finally decided I couldn't go another day without it, so I went yard hopping to get a clock spring and wheel switches that would support it.

After installing the servo, cable, switches, and clock spring, I took the truck for a test and found it wasn't working. Looking at the EVTM, I noted that I didn't have the necessary hydraulic switch on the master cylinder, so I temporarily jumpered the connector and took it for another drive. Still, no luck, so I cracked out the EVTM again to verify continuity and impedances through the clock spring, switches, and vehicle harnesses. Below in yellow are all of the paths I've verified. I also tried a second speed control servo/amp assembly. Is the GEM different for a truck with cruise as opposed to without? Could that be my issue?

Any help is greatly appreciated!

 

[V8 Level II]

There are four ways to cancel the speed control:

Steering wheel switch,
Deactivator switch on the master cylinder,
Brake Pedal Position switch,
Clutch Pedal Position switch (manual only).

Any of the above could be preventing the speed control from working.

You must also have a VSS input to the Speed Control Servo/Module.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


The following self-diagnostic procedure is from the 2002 Ranger shop manual but it works on many Ford years and models.



Do not start engine during this test. Transmission in Park or Neutral with parking brake applied.

Put the key in the ignition and hold the OFF button on the speed control then turn the key to the on position and then release the OFF button. This puts the speed control in diagnostic mode.

Within 5 seconds of releasing the OFF button, start pressing the buttons in the sequence shown below:

• ON
• RESUME
• COAST
• SET/ACCEL

(For each button pressed, the speed control light should flash ONCE, indicating that the pressed button is working.)

If, after pressing the last button (SET/ACCEL), the speed control light flashes:

• 2 flashes - defective brake pedal position sensor and/or a bad clutch pedal position sensor or the circuit is defective.
• 3 flashes - Brake deactivation switch is open or circuit is defective.
• 4 flashes - Vehicle speed signal is out of range or circuit is defective.

Immediately after the last flash code is complete, the speed control servo will pull the throttle open and then release it. This should be watched to check that the throttle and cable are not binding or inoperative for any other reason.

Although it is rare, it is also possible that this code could flash early during the diagnostic procedure.

• 5 flashes – Speed Control Actuator defective.

Turn ignition switch to the off position after test.

Is the GEM different for a truck with cruise as opposed to without?

The 98~2000 GEM is different for a truck with 4WABS vs RABS but should should be the same with or without speed control. As long as you have the speed control VSS input hooked up to a corrected VSS wire (gray/black), that should provide the signal that the speed control needs. Has any of the VSS circuitry been modified in any way? Does the speedometer work?

 

[kimcrwbr1]

Are you getting the proper vehicle speed input?

 

[Rangstang]

To rwenzing: Thank you for the info. I'll try the diags tomorrow and post the results.

I realized that any of the 3 safety switches could've been an issue, that's why I checked continuity through all of them already. I did check through the cruise switches too, but it can't hurt to try again.

To kimcrwbr1: It's a 99 Mountaineer motor, PCM, and engine harness. The signal is coming off the Ranger rear axle just like the Mountaineer.

I swapped a 98 Explorer 5.0 into my other Ranger (99 Ranger XLT) which came with factory cruise and even it worked on my initial test drive and those aren't as compatible as the 99 to 2000...

 

[Rangstang]

The 98~2000 GEM is different for a truck with 4WABS vs RABS but should should be the same with or without speed control. As long as you have the speed control VSS input hooked up to a corrected VSS wire (gray/black), that should provide the signal that the speed control needs. Has any of the VSS circuitry been modified in any way? Does the speedometer work?

You are a wealth of knowledge! Yes, the speedo works fine and I'll have to check on that gray/black wire. When you say corrected VSS, did you mean correct or modified?

Only circuitry intentionally modified is the ground for the tach.

 

[Rangstang]

To rwenzing: I had some time, so I tried running the diagnostics today with poor results. When I pressed "ON", I got the proper speed control light illumination, but nothing for "RESUME", "COAST", or "SET/ACCEL" which led me to believe a possible wiring problem in my wheel since the clockspring wiring for these switches is shared with the "ON/OFF" switch.

I checked resistance by putting probes in pin 5 (light blue/black) and pin 6 (dark green/orange) on the speed control servo and got:

2200 ohms for RESUME
680 ohms for SET/ACCEL
120 ohms for COAST

This proves out the clockspring, switches and harness for that section which brings me back to the other wiring feeding the speed control servo. I've already checked the majority and tried another servo unit, so I'm more that a bit stumped...

 

[V8 Level II]

When you say corrected VSS, did you mean correct or modified?

In 98~2000 Rangers, there is what I call "raw" VSS from the rear axle sensor. The raw VSS is a low voltage analog signal and its frequency depends on the the tooth count of the axle tone ring (different for 7.5 vs 8.8 axles).

This raw VSS signal is sent to a conversion module which corrects for tire diameter and outputs a new signal with a different frequency, amplitude and waveform. The "corrected VSS" output from that module is in the form of a 0~12v square wave that can be read by the speedo, cruise and PCM. If the module has been properly set up for tone ring tooth count and tire diameter, the output frequency will result in 8000 pulses/mile.

Raw VSS --> correction module --> Corrected VSS






There have been several different VSS arrangements used in Rangers over the years.

For 98~2000 Rangers:

The 'correction module' for RABS trucks is the GEM.
The 'correction module' for 4WABS trucks is the 4WABS Module.
All use the rear axle ABS sensor as the source of the raw VSS signal.






The final 0~12v corrected VSS output should be available on the gray/black wire at the PCM, cruise and speedo. If driven very slowly with a voltmeter connected between the GY/BK and ground, the voltage should switch back and forth between roughly 12v and 0. (Go more than a few MPH and the meter won't be able to keep up with the switches and it will display an average value instead.)

 

[V8 Level II]

This proves out the clockspring, switches and harness for that section which brings me back to the other wiring feeding the speed control servo. I've already checked the majority and tried another servo unit, so I'm more that a bit stumped...

Was the wiring to the servo present from the factory or did you have to add it?

 

[hoosier1104]

You have the same problem as me. Look at the 05 Speedo Question thread. It goes into detail for the most part.

Sent from your Grandma's closest using Tapatalk 2

 

[adsm08]

I would like to point out that the lack of the pressure transducer may be contributing to your issue.

I know the diagram makes it look like it is just an open/close switch, but even something as stupid as the switch being there and leaking can cause the cruise to not work.

 

[Riq21]

Can't help with the more technical side of this discussion, but I added my cruise in same circumstance as you several months ago. At first light on dash lit, but cc did not function.. Finally discovered that there was a locking gate that was missing from my cc cable close to the throttle body allowing the cable and cable cover to move back and forth together. Found a clip at the junk yard to fix my problem.

 

[Rangstang]

To rwenzing: Yes, the wiring was there already (oddly enough).

To adsm08: I believe you're referring to the hydraulic switch on the master cylinder, correct? If so, I have one that I can plug in to test since there should be no pressure when the speed control is in effect.

To Riq21: Did your speed control light in the cluster come on when you pressed "SET"?

To hoosier1104: I'll check that thread out.

Thanks for all the input guys.

 

[Rangstang]

To hoosier1104: Okay, keep in mind that my speedometer works fine and has since I did the swap where yours did not and that the VSS is on the rear axle for both the 2000 Ranger and the 99 Mountaineer/Explorer and that the 99-01 5.0 and the 98-00 Ranger are very compatible. As I stated earlier, my 99 Ranger has a 98 Exp 5.0 in it and I had to modify the fuel system and even it's speed control worked out of the box.

 

[Rangstang]

The final 0~12v corrected VSS output should be available on the gray/black wire at the PCM, cruise and speedo. If driven very slowly with a voltmeter connected between the GY/BK and ground, the voltage should switch back and forth between roughly 12v and 0. (Go more than a few MPH and the meter won't be able to keep up with the switches and it will display an average value instead.)

You must be talking an analog meter which I don't have and Harbor Freight doesn't sell anymore either (I checked a while back when I needed one). All I've got is a digital Fluke.

 

[V8 Level II]

You can observe this behavior with a DVM too.

We know that the corrected VSS is present on the GY/BK at the speedometer because it works.

We don't know for sure if the VSS is getting to the cruise servo. My guess is that it is because the servo wiring was there from the factory but it wouldn't hurt to check it and cross that off the list of possibilities.