Ford Repair Questions? Ask a Mechanic for Answers ASAP
There are two switches mounted on the brake pedal ,, one is the stop lamp switch and the other is the deactivation switch ,,, they both look the same ,,, but you should check both
the stop lamp switch is the one with the LIGHT GREEN wire and the LIGHT GREEN / RED wire -----make sure that this switch is not to sensitive ,,,like it the slightest vibration turn on the stop lamps,,,if it is this will cause the cruse to shut off
the deactivation switch has the YELLLOW / LIGHT GREEN wire and the TAN / ORANGE wire ---this switch should have power on both wires when the brake pedal is NOT depressed ,,,if only one wire has power with the brake pedal NOT depressed then the switch is bad ...also make sure that this switch is not to sensitive and you loose power on one of the wires ---you can test this at the cruse servo if you want ,,,unplug the conector to the cruse servo and use a test lamp on the RED / LIGHT GREEN wire ,,,this is the power input wire from the deactivater switch ,,you should have power there all the time until you step on the brake ----you can also test the stop lamp switch input there too,,, it works in the opposite manner ,,, you do not want power there until you step on the brake pedal ,,,this would be the LIGHT GREEN wire at the servo conector
tell me what you find ,,and we can go from there ,,,we can go back and forth on this page
there is also a self test you can do to the cruse system --and its kind of hard to do ,,,you have to do it the right order ,,,you may end up doing it 4 to 5 times before you get it right ,,,,but the cruse lamp will flash a code at you and from the flash you can tell whats wrong ---here is how to do it
Stand-alone speed control system diagnostic updates have been made in 2006 model year and newer Workshop Manuals (WSM). These diagnostic updates also apply to 2000-2005 model year vehicles. This TSB provides these WSM updates for 2000-2005 model year vehicles.
The vehicles in this article are equipped with a 10-pin speed control servo without a standard corporate protocol (SCP) communication control system. Follow the Service Procedures and Diagnostic Tips in this TSB to assist with accurate diagnosis and repair of speed control issues.
Start by running speed control servo integrated self test diagnostics. The servo has integrated self test diagnostics which is a key tool in quickly and accurately diagnosing speed control system faults. Self test diagnostics are also the basis for starting speed control trouble shooting.
The following readings are the expected values for a good servo.
Resistance between Pins 6 and 10 should measure less than 5 ohms. This is the ground circuit through the module. Resistance between Pins 7 and 10 will vary with polarity, the type of meter, and source voltage of the meter. Also measurements between Pins 7 and 10 can be any of the following: an open circuit, increasing reading (as a capacitor charging), or changing value (re-apply leads and different value indicated), or a stable reading of 10,000 ohms or greater are all valid results as this is a solid state circuit.
With the vehicle speed above 30 MPH (48 Km/h) engage the speed control. Then check to see if the TPS PID returns to base voltage when the brakes are applied. If it does return to base voltage, then the speed control system is working. Need to advise customer that tapping the brakes deactivates speed control and that the brakes must be applied to make the vehicle slow down. On the Escape/Mariner the brake pedal should be depressed at least 13/32" (10 mm) in order to deactivate speed control.
Check to see if the TPS PID returns to base voltage when the clutch is pressed. If it does then the speed control system is working. Need to advise customer that pressing clutch deactivates speed control and that the brakes must be applied to make the vehicle slow down.
To verify that the speed control signal sent to the servo is valid, the following inspection may be done for ABS and PCM generated speed signals:
A faulty deactivator switch can result in intermittent or inoperative speed control. There are two types of deactivator switches; a brake line pressure switch, which is integrated into the brake master cylinder, and a pedal travel switch, which is connected to the brake pedal arm.
Proper switch function should be confirmed. Inoperative switches of both types should be inspected for connector corrosion or pin push-out. Pedal travel switches should also be inspected for proper mechanical adjustment relative to brake pedal travel.
PIN 1 - Indicator. (if used) Speed control servo grounds this circuit to turn the speed control lamp in cluster on during operation. This will not affect operation of system.
PIN 2 - Clutch/TRS Input. (Escape/Mariner only) Signal comes from clutch switch (MT) or TRS (AT). On the harness side the signal can be measured by connecting a DVOM, set to ohms, between Pins 2 and B-. With clutch depressed (MT) or in N (AT) you should read 0 ohms, which disables speed control. With clutch released (MT) or in D (AT) signal should read greater than 10,000 ohms, which enables speed control operation.
PIN 3 - VSS Input. (Note: Performed with engine running and vehicle driven.) Signal comes from PCM, ABS, OSS, hall effect sensor depending on application. Except for hall effect sensor, the signal can be measured by removing Connector C122 and measuring the frequency between Pins 3 and 10 with a DVOM set to AC Hz. The signal should measure 2.2 Hz/MPH. The vehicle must be traveling 30 MPH (48 Km/h) before the system will set, therefore a minimum of 66 Hz must be observed. Take note that on vehicles equipped with SVC (speed sensitive volume control), an internal problem within the radio can bring signal down to 0 Hz even though it reads correctly in PCM PIDs. If signal is missing disconnect radio and retest. Note, for vehicles with a hall effect input to the speed control servo, see WSM for speed signal verification.
PIN 4 - Brake Switch Input (BOO/BPP).
Vehicles with automatic transmission and all Escape and Mariner vehicles (auto and manual): With a DVOM set to ohms, measure resistance between Pins 4 and B- with brake pedal not depressed, you should get less than 5 ohms. Then measure voltage with brake pedal depressed, you should get 12 V. Operation: The servo sends out a reference voltage on Pin 4 (4-7V) which is grounded through the brake lamps or switched directly to ground.
Vehicles with manual transmissions (except Escape and Mariner vehicles, see above): With a DVOM set to ohms, measure resistance between Pin 4 and B- with brake pedal not depressed and clutch pedal not depressed, you should get less than 5 ohms. Next, depress clutch pedal only, measuring resistance, you should get an open circuit / infinite resistance. Then measure voltage with brake pedal depressed, clutch pedal not depressed and you should get 12 V. Repeat with both pedals depressed and you should get 0 volts. Operation: The servo sends out a reference voltage on Pin 4 (4-7V) which is grounded through the brake lamps or switched directly to ground when the clutch pedal is not depressed.
PIN 5 - Control Switch Input. (Note: Performed with key in OFF position.) Remove Connector C122, using a DVOM set to resistance, measure the resistance between Pins 5 and 6. See table of resistance readings below for each switch when it is depressed.Figure 3 - Article 06-8-5
PIN 6 - Control Switch Return. This is the return side of the switches, which are grounded internally to the servo to Pin 10. If test for Pin 5 checks good then Pin 6 is functioning normally.
PIN 7 - Power. Remove Connector C122, Using a DVOM set to DC volts, measure the voltage between Pin 7 and ground. You should read greater than 10 volts with the key in the run position. Record the voltage from Pin 7 to ground, then re-measure with a test lamp (1156) from Pin 7 to ground, to ensure current carrying capability. The difference between the two measurements should be less than 0.3 VDC. If voltage drop test fails then check wiring.
PIN 8 - Not used.
PIN 9 - Brake Deactivator Switch (BPS). This is a redundant shutoff switch. Without depressing the brake pedal, measure voltage on Pin 9, and re-measure with a test lamp (1156) from Pin 9 to ground, to ensure current carrying capability. The difference between the two measurements should be less than 0.3 VDC. The system requires enough current at this pin to engage properly. If voltage drop test fails, check for corroded wiring or deactivation switch. You should measure 0 volts at Pin 6 when the brake pedal is depressed firmly.
An alternate to the voltage drop test would be to disconnect the switch connector and measure the switch resistance. It should be less than 5 ohms. If the switch is suspected, a bypass test may also be done: On the harness side of the BPS connector, connect a jumper between the two deactivation switch pins and drive vehicle above 30 MPH (48 Km/h). If speed control engages then the brake deactivation switch was faulty, otherwise wiring is at fault.
PIN 10 - Ground. Using a DVOM set to DC volts, measure the voltage between B+ and Pin 10. You should read greater than 10 volts. Record the voltage between B+ and Pin 10 , then re-measure with a test lamp (1156) from B+ to Pin 10. The difference between the two measurements should be less than 0.3 VDC. If voltage drop test fails then check wiring. This verifies circuit can carry proper load as well as continuity to ground.
NOTE: The information in Technical Service Bulletins is intended for use by trained, professional technicians with the knowledge, tools, and equipment to do the job properly and safely. It informs these technicians of conditions that may occur on some vehicles, or provides information that could assist in proper vehicle service. The procedures should not be performed by "do-it-yourselfers". Do not assume that a condition described affects your car or truck. Contact a Ford, Lincoln, or Mercury dealership to determine whether the Bulletin applies to your vehicle. Warranty Policy and Extended Service Plan documentation determine Warranty and/or Extended Service Plan coverage unless stated otherwise in the TSB article. The information in this Technical Service Bulletin (TSB) was current at the time of printing. Ford Motor Company reserves the right to supercede this information with updates. The most recent information is available through Ford Motor Company's on-line technical resources.
Copyright © 2006 Ford Motor Company
No problem ,, take your time
It could be a cruse switch that is going bad ----but when you do the self test you should notice this ,,,you dont have to have a dsm tool hooked up to the truck to do the test ,, as you are going through the self test every time you push a different button the cruse lamp should light up ,,, and if there was a problem ,,, the light will flash giving you a code ---
sometimes if your driving down the road and you go to activate the cruse and it does not come on ,,,then you really press hard on the cruse switches and then the cruse does come on ,,,then this is a sign of the cruse switches going bad
the two most common things for a cruse system not working sometimes,,, is the deactivation switch and the cruse switches ---other then that I have not seen any other problems