ARM AS- 3708772 - Caterpillar

Continuity Check of the Glow Plugs
The following test will check the continuity of the glow plugs.
Disconnect the power supply and the bus bar.
Use a suitable digital multimeter to check continuity (resistance). Turn the audible signal on the digital multimeter ON.
Place one probe on the connection for the glow plug and the other probe to a suitable ground. The digital multimeter should make an audible sound. Replace the glow plug if there is no continuity.
Check the continuity on all the glow plugs.Checking The Operation of The Glow Plug
The following test will check the operation of the glow plugs.
Disconnect the power supply and the bus bar.
Connect an external power supply to only one glow plug. Connect the negative side of the external power supply to the engine block due to the use of an insulated electric system.
Place a suitable ammeter on the power supply wire.
Table 1
12 Volt System    
Amp    Time (sec)    
16.6     Initial    
12     5.7    
9     11.1    
7     20    
6     60    
Table 2
24 Volt System    
Amp    Time (sec)    
9     Initial    
7     3.3    
6     5.3    
3     60    
Check the reading on each of the glow plugs.
If there is no reading on the ammeter check the electrical connections. If there is still no reading replace the faulty glow plug. If the readings on the ammeter are low replace the faulty glow plug.