need help fan not working

[zman06]

i have 4 mack rolloff trks my 06 mr the fan wont engage when temp is reached cant find temp sensor or where its feed is in fuse panel. it has a new fan clutch and when i unplug the air solenoid the fan will stay on

[Mike Donohue]

Have a manual fan switch? I don't know about 06's , but the CH's used to have the plug behind the panel if not so equipped from the factory and all you had to do was put the switch in and plug the socket in

[Mackpro]

Its controled through the engine ECM. The ECM looks at coolant temp, intake air manifold temp and A/C head pressure ( and can be set up to turn on when engine brake is turned on). Any of these things can turn on the fan. 12 volts comes from the fuse panel and goes through the solenoid to the engine ECM. The engine ECM grounds the solenoid wire to turn on the fan when it sees the correct input from any of the above sensors..

[Deere Mack]

i have 4 mack rolloff trks my 06 mr the fan wont engage when temp is reached cant find temp sensor or where its feed is in fuse panel. it has a new fan clutch and when i unplug the air solenoid the fan will stay on

Welcome. If you changed your air solenoid, you might have plumbed it backwards or it may be bad itself. Also, there's nothing wrong with the fan running all the time, no need to put it on the side line. You might loose some fuel economy, that's it.

[zman06]

Its controled through the engine ECM. The ECM looks at coolant temp, intake air manifold temp and A/C head pressure ( and can be set up to turn on when engine brake is turned on). Any of these things can turn on the fan. 12 volts comes from the fuse panel and goes through the solenoid to the engine ECM. The engine ECM grounds the solenoid wire to turn on the fan when it sees the correct input from any of the above sensors..

ok tks i was hoping it was something simple like a fuse or temp sender on motor

[Hook n ladder 1]

Im having the same problem with my 98 CH. The local shop I use said it's probably the air solenoid. Im going to change that first since it takes all of 2 minutes to do.

[Hook n ladder 1]

ok so I replaced the air solenoid and it didn't correct the problem. Same exact problem as zman. Does somebody have any ideas? Is there a relay somewhere? Is it a ECM problem? Wiring a switch isn't the answer and neither is having the fan run all the time. On a lot of trucks with the air activated clutch...if it runs all the time the clutch overheats and the air line fitting will seize to the hub ( temporarily), spin around and tear the air line off.

Men, your ideas/suggestions are always taken under advisement and never disregarded, so don't take my reply as such.

Thanks for your help.