Engine Hot Alarm / Light Question M923a1

[timntex]

Recently, the alarm / buzzer representing the 'engine hot' warning on my 923a1 started going on in short tones / flashes. Some seem to be longer tones than others. Sounds like Morse code. It doesn't start this until temp reaches normal operating temp range. I checked the coolant level... fine. The temp gauge is within the 185'-190' range depending on outside temp and load. Curious to know if anyone else has had this issue... and if so, what solutions where found to correct it. I've had the truck for two months with no issues until recently. Thanks for the help!

 

[jumpmasterjim]

Check to see if the fan is spinning. the clutch fan could be bad.

 

[timntex]

Fan spins... appears to be in working order.

 

[juanprado]

Some of the early models had a temp light but the military decided against using it. Most trucks do not have a light on the dash warning strip above the wheel. Does yours have a temp light?

I wonder if your fail safe alarm if failing that senses parking brake on and low air brake pressure? Only buzzer I was aware of unless the original temp light also had a separate buzzer? I have not seen either on the tm's.

Erick's shows the following on the fail safe part description on the wiring codes:

Connector wiring:
A, from engine ignition circuit
B, blackout override input
C, not used
D, to engine temp switch
E, to engine over temp light
F, to air pressure switches
G, to low air warning light
H, ground
I, to parking brake switch
J, to parking brake warning light

I wonder if this could be the problem many of us are experiencing with this part buzzing when nothing obvious is wrong when the temp function was bypassed?

http://www.eriksmilitarysurplus.com/faalform9set.html

 

[timntex]

Thanks for the help. Mine defiantly has the temp light on the strip above the wheel. As for parking brake alarm, when brake is applied sometimes it works and at times it doesn't. So far that is it in regards to the buzzer alarm going off expectantly.