dangonzo
Junior Member
- Joined
- May 22, 2017
- Posts
- 18
- Reaction score
- 4
- Location
- Connecticutt
- First Name
- Daniel
- Truck Year
- 1981
- Truck Model
- C10
- Engine Size
- 305
While replacing the heater core I decided to try to figure out why my blower motor doesn't work. I tried to narrow down the issue but am having trouble so maybe somebody can help me figure it out.
The fuse appears to be fine.
There is power from the switch in every position except for low. I tested this with a test light and when the switch is on high, medium high, and medium low, I get a signal at the corresponding wire.
There is power to the blower motor from the wire coming off the relay.
So from that it felt like everything was in order (with the exception of the switch not giving power to the low wire). So I hooked the blower motor up directly to the battery positive and grounded it to the battery as well and the blower motor ran fine.
I figured that meant that the motor itself was fine, and the issues were coming from the power from the relay or the ground that the motor uses. But after hooking up the multimeter to the power wire coming from the relay and the ground the motor uses I got 12.34V with the switch in the on position.
Next, I ran a jumper wire from the battery positive to the motor and used the ground that the motor normally uses and received no response from the motor.
Then I did the opposite and used the power from the relay and grounded the motor with the battery negative terminal. I saw a spark at the ground on the motor but nothing else. I don't really know what this should be telling me.
Can anybody help me with what to do next?
The fuse appears to be fine.
There is power from the switch in every position except for low. I tested this with a test light and when the switch is on high, medium high, and medium low, I get a signal at the corresponding wire.
There is power to the blower motor from the wire coming off the relay.
So from that it felt like everything was in order (with the exception of the switch not giving power to the low wire). So I hooked the blower motor up directly to the battery positive and grounded it to the battery as well and the blower motor ran fine.
I figured that meant that the motor itself was fine, and the issues were coming from the power from the relay or the ground that the motor uses. But after hooking up the multimeter to the power wire coming from the relay and the ground the motor uses I got 12.34V with the switch in the on position.
Next, I ran a jumper wire from the battery positive to the motor and used the ground that the motor normally uses and received no response from the motor.
Then I did the opposite and used the power from the relay and grounded the motor with the battery negative terminal. I saw a spark at the ground on the motor but nothing else. I don't really know what this should be telling me.
Can anybody help me with what to do next?
