Blower motor only works on1,2,3,4 but no 5 or high speed

The blower motor relay is energized when the Blower Motor Control is set to the High position. This removes the blower motor resistors from the circuit and battery voltage is then applied directly from the HVAC BLO fuse (RH IP Accessory Wiring Junction Block) to the blower motor though the relay switch contacts. The blower motor then runs at high speed.

HVAC Blower Controls Circuit Description
The blower motor is a variable speed motor. The motor operates at a higher rate when voltage is increased to the maximum level.
The blower motor resistors reduce the voltage supplied from the A/C FAN fuse (LH IP Accessory Wiring Junction Block) when the blower control is set at low and medium speeds (speeds 1-4). The blower motor relay is energized when the Blower Motor Control is set to the High position. This removes the blower motor resistors from the circuit and battery voltage is then applied directly from the HVAC BLO fuse (RH IP Accessory Wiring Junction Block) to the blower motor though the relay switch contacts. The blower motor then runs at high speed.

Could be a number of thing's ! Testing the electrical circuit is the way to find out what's wrong . Using a wiring diagram and a DVOM - digital volt ohm meter . Videos on youtube showing how to test it ! Without testing i would only be guessing . Does it work in high speed ? In high speed it by-passes the resistor . If it doesn't work in any speed more then likely the blower motor is the problem !
Air Speed
The HVAC control assembly applies ground to the blower motor control circuit that corresponds to the selected blower speed. The resistors and the blower motor are in a series circuit. The following list represents the number of resistors in series with the blower motor per particular speed request:
• Low speed--3 resistors
• Medium 1 speed--2 resistors
• Medium 2 speed--1 resistor
When the operator requests High speed, the HVAC control assembly applies ground directly to the blower motor through the high blower motor control circuit. The resistor card has a fusible link which, if blown, will require that the card be replaced.

Blower Motor and Resistor Diagnostics by Wells

Its faulty blower motor resistor. The low and medium speed on blower motor is controlled by resistor and its actual speed is high. So because resistor is not working, blower motors actual speed which is high is working.

It can be faulty blower motor or faulty blower motor resistor. Get the blower motor inspected. If it's faulty it has to be replaced.

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For blower motor testing and replacing, check the link below: ----

Blower motor Testing/replacing for all vehicles?

http://repairhelpcenter.blogspot.in/2012/02/blower-motor-replacing-for-all-vehicles.html

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These will help.

Thanks.

Its faulty blower motor resistor. The low and medium speed on blower motor is controlled by resistor and its actual speed is high. So because resistor is not working, blower motors actual speed which is high is working.

It can be faulty blower motor or faulty blower motor resistor. Get the blower motor inspected. If it's faulty it has to be replaced.

=======

For blower motor testing and replacing, check the link below: ----

Blower motor Testing/replacing for all vehicles?

http://repairhelpcenter.blogspot.in/2012/02/blower-motor-replacing-for-all-vehicles.html

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These will help.

Thanks.

HEATER BLOWER MOTOR

Its faulty blower motor resistor. The low and medium speed on blower motor is controlled by resistor and its actual speed is high. So because resistor is not working, blower motors actual speed which is high is working.

It can be faulty blower motor or faulty blower motor resistor. Get the blower motor inspected. If it's faulty it has to be replaced.

=======

For blower motor testing and replacing, check the link below: ----

Blower motor Testing/replacing for all vehicles?

http://repairhelpcenter.blogspot.in/2012/02/blower-motor-replacing-for-all-vehicles.html

------------

These will help.

Thanks.

check fuses, then wiggle speed control while moving, may need new dash control for lower speed, usually high speed works through relay may be the reason high speed works

Hi!!
The Blower Motor Resistor also called Manual Temp. Control resistor), is fried, replace. The price with floor console $25 and without floor console $65. here is a pic.


the resistor is located on the blower motor housing, fastened by two screws. It is the part where the electrical plug connects, the plug on the pic. goes to the blower motor.
A HELPFUL - 4 THUMBS rating for this solution would be greatly appreciated. Thank you for using FixYa.

more than likely yes the resistor

Disconnect connector at blower under pass side of dash.Check for power & ground with the blower switch in the #4 speed (High).Most Likely a blower motor if all 4 speeds are out.If high works but no other speeds,you need a blower resistor.Blower easy to change 3 screws & one connector.hope this helps

yes, all blower motors have them to control their speed, High, medium, low.. etc. I earn nothing by helping you, but my rating, a fixya rating and I will walk you through this