1989 Buick Riviera overheats

1989 BUICK RIVIERA
20,000 MILES • 6 CYL • 2WD • AUTOMATIC
Avatar
RUSTY BAKER
  • MEMBER
  • 1 POST
My cooling fans don't come on when they should. Have replaced the heat sensor and all fan relays. Both fans have been tested and do work, The thermostat seems to open okay. Don't know what to check or replace.
Oct 8, 2009 at 8:12 PM
Advertisement
Avatar
DOCFIXIT
  • ✓ASE Certified Mechanic
  • 18,828 POSTS
  • ASE Certified Mechanic
The ECM grounds relays in response to temp and AC input. So if relays not clicking in and power is there then ECM or wiring is at fault.
Oct 9, 2009 at 10:46 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.