Mechanics

ALTERNATOR AND HEATER BLOWER NOT WORKING

2000 Ford Ranger

Electrical problem
2000 Ford Ranger 4 cyl Two Wheel Drive Manual 130000 miles

had a problem with the heater blower only working on high setting. Began checking the engine compartment fuses- all OK- started the truck and discovered that the alternator was not charging. Replaced the alternator - new one not charging either. Rechecked the fuses, all appear good. Checked the hot lead on the rear of the alternator-battery voltage present-12volts. I'm sure that I caused the problem by pulling and checking the fuses, but can't find the problem

Thanks
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Sylvester95
April 6, 2009.



First off I think you blower motor problems is probably the blower motor resistor in the heater box as this controls motor speed with different resistance. So lets get to the Alternator first and get to that after we have charge ok. Now first I know you check the fuses but I need you to do this again but first I need you to check the alternator fuse that is in the battery junction box it is 30 amp make sure it is good. Now check the mega fuse this is 175 amp fuse and it is at the battery junction box too it is between the main battery lead to the junction box and the alternator wire. Let me know what you find and we will go from there.

Racefan966
Apr 7, 2009.
Racefan966: checked the 30 amp fuses in the engine distribution box - all are OK. Unable to locate the 175 amp fuse. The box containes 2- 50 amp fuses, and 1- 40 amp, nothing larger. These fuses are good also. Could the mega fuse be located elsewhere? I traced the leads from the battery to the distribution box, could find nothing in between. Thanks

Tiny
Sylvester95
Apr 7, 2009.
Ok according to the wiring diagram the Mega fuse is on the outside of the power distribution center under the hood on the drivers side. Now this fuse is the link between the battery wire and the black wire with the orange strip that goes to the alternator. So what you can do is get a test light or better would me a multi meter and check the black/orange wire at the alternator and see if battery voltage is there. Then check the Yellow wire at the alternator and see if it has battery voltage. Now I need you to check fuse number 15 in the fuse panel inside the truck it is a 7.5 amp fuse. If it is good then I need you to check light green wire with the red stripe to see if it has power to it, now this one may only have power when the key is on. Get back to me and let me know what you find.

Racefan966
Apr 8, 2009.
The 7.5 amp fuse in the dash fuse panel was blown!

It was not visually apparent, but showed bad when checked with my multi-meter. I'll replace the blower resistor-should solve the blower speed problem.

Thanks for the assistance, your expert advice led me to the solution.

Tiny
Sylvester95
Apr 8, 2009.
Great glad to hear it is fixed and working right. If you have any more questions just ask. Thanks and have a Great Day.

Racefan966
Apr 9, 2009.