Question about 2000 Mercury Grand Marquis
The fan stopped working regardless of the speed being set low or high, heat, A/C, vent, etc. I checked all the fuses, took the climate control unit from the dash, checked and cleaned all connections. disconnected the blower motor and measured the voltage. At low speed, I was receiving 2-3 volts and at high fan speed, 10-12 volts. I figured the motor was bad so I replaced it, but got the same problem. I took both the new and old blower motors and applied external battery and both motors worked. I figured maybe the connector itself was bad so I cut the wires and connected directly to the motor and it still did not work. When I checked the voltage with the motor attached, I was not getting any reading. Something is causing a voltage drop when the motor is connected, but I don't know how to proceed?
I had the same problem with my 2000 Mercury Grand Marquis. I ended up replacing the blower and the resistor which is on the passenger center side of the firewall tucked in where it is hard to get to. Everything worked fine for about two years. It just went out again here about a month ago. I am going to try to replace the resistor again, but I am wondering if it doesnt have something to do with the climate control switch. I do not want to replace the same part every year or two, so if anyone has a idea of what could possibaly be the bigger problem, please let me know.
Posted on Nov 22, 2008
I know this is gonna sound stupid but you mentioned nothing about it did you by chance find and check for a ground ?
Posted on Aug 15, 2008
SOURCE: heat-a/c blower motor stopped
check for ground going to fan. If there is no ground replace a/c control panel located under radio it what you use to turn on the heater/ a/c
Posted on Aug 27, 2008
It's even odd that you were getting a step-type voltage when you first checked.
Many speed regulators are simple tapped resistors with the switch selecting which tap is connected to the motor.
More elegant controls would use a semiconductor (transistor) and a few other components to supply step-variable voltage to the motor.
To determine which is used on your car, you will at least need the electrical diagram for it, preferably an aftermarket service manual - Haynes or Chilton should be available at least in the US and Canada.
Those will contain not only the electrical info you now lack but possibly instructions that will aid in locating the controlling circuit.
I suspect that circuit is faulty; if the resistor type, it will be a device with mulitple taps, if solid state, a few parts on a small board.
Posted on Jun 18, 2008
Tips for a great answer:
Feb 23, 2015 | Nissan Cars & Trucks
Feb 09, 2013 | 2005 BMW 545i
Oct 30, 2011 | 1997 Lincoln Continental
May 03, 2011 | 1997 Ford Contour
Nov 01, 2009 | 1999 Volvo V70
Jun 16, 2009 | 1996 Subaru Legacy
Oct 07, 2008 | 1997 BMW 328
Jun 18, 2008 | 2000 Mercury Grand Marquis
696 people viewed this question
Usually answered in minutes!