cooling fan

1998 MERCURY MYSTIQUE
4 CYL • FWD • AUTOMATIC
Avatar
KELCIE
  • MEMBER
  • 2 POSTS
What causes the cooling fan to run at high RPMs in a 1998 mercury mystique? i put a new thermostat in the engine and now the fan runs constantly and will not shut off. Please help me!! need advice! do not know what to do in order to fix this problem
Nov 18, 2010 at 6:15 PM
Avatar
JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,246 POSTS
The fan is actuated as the result of a couple things. First, the temp sensor sends a signal the PCM (computer) telling it what the coolant temp is. Once it reaches a certain temp, the computer sends power through the fan relay which then sends power to the fan motor. If they are running all the time, you could have a bad relay, temp switch, short in the wiring...
Nov 18, 2010 at 6:26 PM
🔧 Tools & Auto Repair Parts
Find automotive tools, diagnostic equipment, and replacement parts for your next repair.
Shop on Amazon →
Paid affiliate link. As an Amazon Associate, we earn from qualifying purchases.
Add a reply
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 new question

Frequently Asked Problems for This Vehicle