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+--- Thread: Cascadia cab blower motor (/showthread.php?tid=5868)
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Cascadia cab blower motor - sprayerman - 02-23-2020
Blower motor in my 2014 cascadia quit working... I don't seem to have any power to it. Not sure why, what am I missing? Any ideas?
I did have a Dash PWR RCPT 1, BAT fuse blown but that did not solve the problem and am assuming that's unrelated.
RE: Cascadia cab blower motor - Waterloo - 02-23-2020
Could be the HVAC control head unit. Mine has failed in my ProStar twice. One thing to do is see if power is actually getting to the blower motor, a simple 12 volt tester will work. Disconnect the plug from the blower, stick tester into harness plug, test both sides, as one is a ground, turn off HVAC, turn on HVAC, if the light on your 12 volt tester lights up, odds are you need a new blower motor. No light, could be the HVAC head unit is bad. Odds are it is your blower motor, they are all made in China and the quality of the old USA units is no longer there.
I buy mine here, http://www.truckersac.com
These guys are great, they are in Atlanta and ship the same day. Hard to beat their prices, most parts are OEM. I have had good luck with everything I have purchased from them, which has been quite a bit.
RE: Cascadia cab blower motor - sprayerman - 02-23-2020
(02-23-2020 )Waterloo Wrote: Could be the HVAC control head unit. Mine has failed in my ProStar twice. One thing to do is see if power is actually getting to the blower motor, a simple 12 volt tester will work. Disconnect the plug from the blower, stick tester into harness plug, test both sides, as one is a ground, turn off HVAC, turn on HVAC, if the light on your 12 volt tester lights up, odds are you need a new blower motor. No light, could be the HVAC head unit is bad. Odds are it is your blower motor, they are all made in China and the quality of the old USA units is no longer there.
I buy mine here, http://www.truckersac.com
These guys are great, they are in Atlanta and ship the same day. Hard to beat their prices, most parts are OEM. I have had good luck with everything I have purchased from them, which has been quite a bit.
I have already checked for power at blower plug. I got nothing. Maybe it is the control head but I think otherwise it's functioning correctly.
RE: Cascadia cab blower motor - Waterloo - 02-23-2020
Have you bench tested the blower motor?
Check the power to the HVAC head unit too. Could be a crimped or shorted wire somewhere in the dash. And replace any fuses, if they tarnish they will test out fine, but in reality they do not work.
RE: Cascadia cab blower motor - bwake - 02-25-2020
Check the blower motor relay in the dash and make sure that it's functioning properly. Pins 85 and 86 will be the coil side which is going to be controlled by the switch. Pin 30 will have constant power and 87 will be the switched power going to the motor. A simple check is to jump across pin 30 and 87 and see if you now have power at the motor. If 30 has power and jumping to 87 still gives you nothing at the motor, you're going to need to check your blower motor relay which will be in the duct work just after the blower motor.
RE: Cascadia cab blower motor - sprayerman - 02-26-2020
(02-25-2020 )bwake Wrote: Check the blower motor relay in the dash and make sure that it's functioning properly. Pins 85 and 86 will be the coil side which is going to be controlled by the switch. Pin 30 will have constant power and 87 will be the switched power going to the motor. A simple check is to jump across pin 30 and 87 and see if you now have power at the motor. If 30 has power and jumping to 87 still gives you nothing at the motor, you're going to need to check your blower motor relay which will be in the duct work just after the blower motor.
Can you tell me where the blower motor relay is? Also does anybody have a wiring diagram for the cord end that plugs into the motor?
RE: Cascadia cab blower motor - sprayerman - 02-26-2020
(02-23-2020 )Waterloo Wrote: Have you bench tested the blower motor?
Check the power to the HVAC head unit too. Could be a crimped or shorted wire somewhere in the dash. And replace any fuses, if they tarnish they will test out fine, but in reality they do not work.
As far as doing a bench test on the motor. I have to supply battery power and speed signal correct?
RE: Cascadia cab blower motor - Chamberpains - 02-26-2020
Ya, a 12v feed and a simple rheostat (cheap 12v dimmer switch) to run through its range and of course the ground.
RE: Cascadia cab blower motor - bwake - 02-26-2020
(02-26-2020 )sprayerman Wrote:(02-25-2020 )bwake Wrote: Check the blower motor relay in the dash and make sure that it's functioning properly. Pins 85 and 86 will be the coil side which is going to be controlled by the switch. Pin 30 will have constant power and 87 will be the switched power going to the motor. A simple check is to jump across pin 30 and 87 and see if you now have power at the motor. If 30 has power and jumping to 87 still gives you nothing at the motor, you're going to need to check your blower motor relay which will be in the duct work just after the blower motor.
Can you tell me where the blower motor relay is? Also does anybody have a wiring diagram for the cord end that plugs into the motor?
Scratch all the prior info, didn't look at the year and none of that applies to your truck. For some reason I can't attach the wiring diagram so I'm going to do my best to explain it here:
Power feeds from the cabin HVAC control panel through wire #98 (lt blue pin 4), ground (black pin 5), and ignition power #81c (pink pin 6) these are what feed the Sam Cabin Module (pins 3, 14 and 10).
Sam cabin module sends 12v through wire 98f (lt blue, pin 4) and ground (black, pin 2) directly to the blower motor plug.
The other 2 wires going to the blower motor come from HVAC control panel which are wires 338m (pin #23) which is the blower diagnostic wire and 338h (pin #24) which is the blower speed control.