Heater fan wont blow on any setting on 2002 gran prix pontiac?

When you replaced the ECM did you have it reprogrammed?

check relay fuse to ur blower under the hood

most a/c fans are usually located into the a/c heater box assembly most vehicles are inside behind the glove box area some are in the engine compartment at the firewall .generally not to bad to fit.regards agwbk

If leaking coolant under dash on passenger side floor broad it's your heater core. Call's for 2.8 labor flat time to remove heater core, in some case's you'll have to recover, evacuate and recharge your A/C system to remove your heater core.Sit under dash on passenger side.

for the fan blower motor it could be the resistor or the fan control speed control switch is bad.for no lights replace the DRL RELAY for the lights. for the heated seats check the fuses.

THE BLOWER MOTOR RESITOR IS BAD.IF U HAVE RESITOR IT IS UNDER THE DASH ON THE PASSENGER SIDE AND HELD IN W/TWO SCREWS

There is a flat filter that sits between the firewall and the blower. Sometimes the filter is blocked and needs to be cleaned or changed. On older cars the filter is located on the firewall in the engine compartment infront of the blower. In the newer cars the filter is under the dash inside the car and much harder to get too.,

No solution found as of yet.

i do believe you have to take the passengers side dash apart behind the glove compartment. go to autozone and get a manual or go to the library and check the chiltons manual. this is not an easy job. how bad is the leak? if its not bad these heater cores are made of all aluminum. i would buy a bottle of that radiator additive and see if that takes care of the problem first. it only cost about 5 bucks a bottle and it may permanantly fix your problem.

I would suggest replacing the blower motor resistor. When this component fails the blower will only work on one spped or none. This is a very common issue with all automotive models