FJ40 Rear Heater Fan - only one speed (2 Viewers)

[stoshzack]

Bypassing the resistor in low speed worked (I.e. ran on high). So it is either the resistor or a bad ground. Working on adding some more ground locations to the vehicle. My normal ground is spotty. I unbolted the heater and ran an alligator ground clip to the mounting hole/bolt. Some times it ran, other times it did not.

 

[1969FJ]

Bypassing the resistor in low speed worked (I.e. ran on high). So it is either the resistor or a bad ground. Working on adding some more ground locations to the vehicle. My normal ground is spotty. I unbolted the heater and ran an alligator ground clip to the mounting hole/bolt. Some times it ran, other times it did not.

Does your resistor have any numbers on it ?

 

[stoshzack]

Does your resistor have any numbers on it ?

I do not think so, but I will check and let you know.

 

[Living in the Past]

Before I did any work on grounding I would perform this test first. Run a wire directly from the battery ground right by the rear heater but not attached to the motor. When it on low speed trying grounding the motor to see if will run. Next while on high speed check to see if the motor speeds up. This will let you know what to expect working on the ground. Prior to the test would check the voltage at the battery with the engine running. This will help verify the ground from the battery to the chassis is good. If the starter is not struggling to start the battery ground is probably good.

 

[POPO AGIE]

I has been a very long time since my rear hear was used but it seems it only came on when I pulled the switch out to the second detent or I just couldn't hear it on low.

I let my Ex sister in-law use it to drive out to sheep camp for English lessons and she complained about the cab being cold. We both jumped in an went for a ride and I pulled the switch all the way out and there was more heat then we need in the cab.

 

[stoshzack]

Rear heater is like the front heater. If it's a two speed it will have a resistor by the heater motor not in the switch. High speed wire is soldered to the same side and the motor winding wire. Low speed is soldered on the other side of the resistor so in low speed it's in series with the resistor. High speed bypassed the resistor.

Does your resistor have any numbers on it ?

This should help. See second and third pages.

Two speed rear heater.

Rusty72 My oem resistor gets very hot when on low speed. It looks like it's supposed to. Ceramic coating? I had to solder the edge earlier to get it to work due to looseness and corrosion I think all resistors give off heat? Nature of the beast? Like an electric stove? Cooler man would know...

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