[Rick1803]

1993 164L. Radiator cooling fan not working on low speed. I have read previous posts, very helpful as usual. I'm studying the wiring diagram on Car Disc. Can anyone tell me what the wire identifications mean, particularly the numbers? For example, 6RED ? I think RED is the color, but what does the 6 mean ?

Thanks
Rick

 

[Alfisto Steve]

1993 164L. Radiator cooling fan not working on low speed. I have read previous posts, very helpful as usual. I'm studying the wiring diagram on Car Disc. Can anyone tell me what the wire identifications mean, particularly the numbers? For example, 6RED ? I think RED is the color, but what does the 6 mean ?

Thanks
Rick

Size of wire as in 6mm which is equal to size 8 AWG (American wire gauge).

Brown wire to low speed resistor is 2.5mm as is blue wire to othe side of resistor.

If fan not working on low maybe resistor in fan shroud bad try jumping 2.5 blue to 2.5mm brown.

 

[Rick1803]

I do think the resistor has failed. I performed tests in other threads: unplugged thermal switch, then used paper clip to jump black to brown-white, the fan runs on high. Then paper clip to jump black to brown, relay clicks but fan doesnt run.

If I jump 2.5mm blue to 2.5mm brown (bypass resistor?) I think I will overlaod the 2.5 wires. Bypassing the resistor this way simply provides redundant high speed supplies. Shouldn't high speed have 6mm - 40A wire ?

I saw your thread where you swap brn and brown-white relay control. That does protect against overlaod. But you dont need to bypass resistor if you do that. Now the low temperature (198F) contact in thermal switch controls the high speed relay with the correct wire size (larger). The low speed relay and (bypassed) resistor are not utilized, unless the temp goes to 206F, but the fan is already running on high.

Thanks
Rick

 

[Alfisto Steve]

I do think the resistor has failed. I performed tests in other threads: unplugged thermal switch, then used paper clip to jump black to brown-white, the fan runs on high. Then paper clip to jump black to brown, relay clicks but fan doesnt run.

If I jump 2.5mm blue to 2.5mm brown (bypass resistor?) I think I will overlaod the 2.5 wires. Bypassing the resistor this way simply provides redundant high speed supplies. Shouldn't high speed have 6mm - 40A wire ?

I saw your thread where you swap brn and brown-white relay control. That does protect against overlaod. But you dont need to bypass resistor if you do that. Now the low temperature (198F) contact in thermal switch controls the high speed relay with the correct wire size (larger). The low speed relay and (bypassed) resistor are not utilized, unless the temp goes to 206F, but the fan is already running on high.

Thanks
Rick

You are correct both counrs.

Bypassed resistor jumpered 2.5mm wires do get hot with 6mm wire feeding them which is why I do switch over relay control wires in relay socket holders so a/c and low temp rad switch runs fan on high relay using 6mm in and out brown and black wires.