Cruise Control Troubleshooting - Ford Truck Enthusiasts Forums

1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

Cruise Control Troubleshooting

Thread Tools Search this Thread
Old 02-16-2003, 01:36 AM
whatthemonkey whatthemonkey is offline
New User
Thread Starter
Join Date: Dec 2001
Location: Hobbs, America
Posts: 6
whatthemonkey is starting off with a positive reputation.
Cruise Control Troubleshooting

I have had great luck asking questions in this forum, so here I go again: the cruise control in my 1988 F-150 (L6, 5-spd) suddenly stopped working with no warning of any kind. I figured it was the servo, and since it seemed cheapest and easiest to change, I bought a remanufactured one and put it in. The cruise still does not work. The buttons in the steering wheel are getting power and they all pass on different voltages (purposely I presume) so I do not know what to check next. I noticed one other threat about a cruise control, but it did not get to a solution. If anyone has any ideas, maybe even an order to check things, I would greatly appreciate your assistance. Thank you for your time.
1988 F-150 4.9L L6
Reply With Quote
Old 02-16-2003, 11:00 AM
steve83's Avatar
steve83 steve83 is offline
Post Fiend
Join Date: Nov 2002
Location: Memphis, TN
Posts: 9,987
steve83 is starting off with a positive reputation.
Cruise Control Troubleshooting

The Haynes manual shows the wiring for the cruise system, so check it out.

There is a small Vehicle Speed Sensor stabbed into the t-case where the speedo cable connects, and it sends pulses to the cruise computer. Older ones were prone to locking up or breaking, but '87-92 VSSs were pretty good. Pull yours (it's easy & intuitive) and put the speedo gear into a drill and see if it's producing a tiny A/C voltage (should change with drill speed). It should spin VERY freely.

A more likely cause would be a loss of vacuum supply to the servo (check the hoses for leaks) or a leak in the line that goes thru the firewall to the brake pedal valve. If that valve is leaking or its line is, the servo will always think you're trying to stop, and it won't engage.
Reply With Quote
Old 02-16-2003, 12:07 PM
dbrown13 dbrown13 is offline
Senior User
Join Date: Sep 2001
Location: Central Texas
Posts: 291
dbrown13 is starting off with a positive reputation.
Cruise Control Troubleshooting

to check is the cutout switches on the brake/clutch pedals.
Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Cruise control not holding speed mksnipe 1999 to 2016 Super Duty 11 12-15-2015 08:22 AM
1988 F150 Cruise Control Will Chiello 1987 - 1996 F150 & Larger F-Series Trucks 0 12-03-2011 11:33 AM
steering wheel for cruise control-1988 F250 wrd0225 Pre-Power Stroke Diesel (7.3L IDI & 6.9L) 1 02-11-2011 06:46 AM
89 F150 cruise control not working TommiFIN Electrical Systems/Wiring 2 06-30-2008 03:57 AM
1994 F-150 cruise control Domino Electrical Systems/Wiring 4 02-11-2003 11:21 PM

Go Back   Ford Truck Enthusiasts Forums >

1986, 1994, control, cruise, diagram, f150, ford, rebuilt, servo, steve83, troubleshoot, troubleshooting, truck, vacuum, wiring

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

All times are GMT -5. The time now is 03:14 PM.