Rad fan not coming on

[davery]

So I recently replaced my master cylinder and afterward I am having a few issues. I am not sure if they are related, so I thought I would ask. The radiator fan is not coming on, the speedometer is not working (although all other gauges are working) and the clock has no power. I also noticed two wires (brown and white) around the fuse box that are not connected to anything. The two wires come together and have a clip like they should slide into something but I cannot find anything around for it to connect to. With all the knowledge on this website, I thought I would ask. Are these related? Anyone know what these wires are to? Any ideas of where to start?

[RRoller123]

Got a schematic? It sounds like something got disconnected when the master cylinder was being changed, maybe wiring harness got tugged.

[davery]

Got a schematic? It sounds like something got disconnected when the master cylinder was being changed, maybe wiring harness got tugged.

I looked around the engine bay and did not see anything. That was my first thought. I amy have a schematic in the shop manual. I will have to track it down.

[rodman]

Here is PDF I uploaded to out Facebook group[ http://www.facebook.com/download/226939 ... 0_1982.pdf

[RRoller123]

The speedo not working after replacing the MC indicates most likely that the cable was pulled and the end has come out of the back of the speedo.

[davery]

The speedo not working after replacing the MC indicates most likely that the cable was pulled and the end has come out of the back of the speedo.

That is what I sort of thought. I would assume that means these are unrelated.

[TX82FIAT]

Looks like you will need the schematic. The cooling fan is a constant power hooked to a thermo cooling switch. Your black ground wire coming off the cooling fan goes to the cooling fan thermo switch, that switch then has a black ground wire coming off of it. The connection point outside the cooling fan thermo switch can be bypassed with two alligator clips to complete the circuit and turn the fan on. If the fan goes on with this bypass you do not have a circuit problem but either a thermo switch problem (common and quick to fix) or some other problem that is preventing the lower rad from getting to heat such as air in the cooling system.

white and brown wires.. I think are ignition switch wires? the clock power wire is red/black?

I think some of your issues may be unrelated. However, have you checked all your grounds?

[davery]

Looks like you will need the schematic. The cooling fan is a constant power hooked to a thermo cooling switch. Your black ground wire coming off the cooling fan goes to the cooling fan thermo switch, that switch then has a black ground wire coming off of it. The connection point outside the cooling fan thermo switch can be bypassed with two alligator clips to complete the circuit and turn the fan on. If the fan goes on with this bypass you do not have a circuit problem but either a thermo switch problem (common and quick to fix) or some other problem that is preventing the lower rad from getting to heat such as air in the cooling system.

white and brown wires.. I think are ignition switch wires? the clock power wire is red/black?

I think some of your issues may be unrelated. However, have you checked all your grounds?

Thanks for the info. Any idea where the cooling fan thermo switch is located?

[courtenay]

The switch is located at the bottom of the radiator - on the inside. It will have two wires coming out of it.

[4uall]

[weekend warrior]

A simple check to see if its the fuse for the rad fan is to press the horn button, they are both on the same circuit.

[davery]

A simple check to see if its the fuse for the rad fan is to press the horn button, they are both on the same circuit.

Horn works, need to check the thermo switch.

[davery]

A simple check to see if its the fuse for the rad fan is to press the horn button, they are both on the same circuit.

Horn works, need to check the thermo switch.

I got the fan to come on. So does than mean it is the switch? Nothing else could cause the fan not to run when the car is hot?

[azruss]

if you jumpered across the thermo switch and the fan went on, then all is well with the system except the thermo switch. this switch may be ok if the bottom of the radiator is staying cold. If that is the case, you have a circulation issue, usually the thermostadt isnt opening.

[RRoller123]

Just an idea... It is possible that the car was configured with a manual overide switch, as many POs did in the past when unable to resolve fan cooling problems. Mine came with this. If you see a small switch typically somewhere under the dash, driver's side, near the fuse box, that may indicate what is going on. After resolving the thermoswitch, burping, gauge sensors, and wiring problems( ) I just left the overide in place, properly wired as a backup.