0111-11 Very Low Coolant Level (62)

127

TM 9-2320-312-24-2

Troubleshooting Section

GMT-560 applications have the option of using a

i01725052

2-pin switch to monitor coolant level. To use a 2-pin

0111-11 Very Low Coolant

switch, the parameter "Manufacturer/Model" must

Level (62)

be programmed to "GMT-560" and the parameter

"Coolant Level Sensor" must be programmed

to "2-pin switch". The diagnostic fault codes for

SMCS Code: 7422-038

the coolant level sensors are disabled when the

"Coolant Level Sensor" parameter is programmed

Conditions Which Generate This Code:

to "2-pin switch". The switch is connected to

P1/J1:49 ( coolant level switch) and to P1/J1:5

This condition indicates that the coolant level is

(AP sensor/switch sensor common). If the coolant

very low. "Engine Monitoring" must be programmed

level is normal, the switch should be closed and

to "WARNING", "DERATE", or "SHUTDOWN", and

P1/J1:49 connected to ground. The warning lamp

the parameter "Coolant Level Sensor" must be

will be illuminated via the J1939 data link when the

programmed to "4-pin", "2-pin switch", or "2-wire

coolant is low.

float sensor" before this diagnostic code can occur.

Test Step 1. Check the Level of the

Note: This diagnostic code represents a critical

Coolant

event. This diagnostic code does not represent an

electronic system fault.

Visually check the level of the coolant. Ensure that

the coolant level switch is fully immersed in the

System Response:

coolant.

Electronic System Response If the "Engine

Expected Result:

Monitoring" is programmed to "DERATE" or

"SHUTDOWN", the ECM will derate the power and

The coolant is at the proper level.

the ECM will limit the vehicle speed due to this

diagnostic code.

Results:

If "Engine Monitoring" is programmed to

OK Proceed to Test Step 2.

"WARNING", the Check Engine Lamp will flash and

the Warning Lamp will illuminate continuously.

Not OK

If "Engine Monitoring" is programmed to "DERATE"

Repair: Fill the cooling system with the proper

or "SHUTDOWN", the Check Engine Lamp and the

coolant to the correct level. For further information,

Warning Lamp will flash.

refer to the Operations and Maintenance Manual.

This diagnostic code requires a Customer Password

STOP.

in order to be cleared.

Test Step 2. Inspect Electrical Connectors

Service Tool Display or Lamps Caterpillar

and Wiring

Electronic Technician (Cat ET) will display "LOW"

and "DIAG" next to "Engine Coolant Level" on the

A. Thoroughly inspect the following connectors:

status screen while the diagnostic code is active.

J1/P1 ECM vehicle harness connector

Engine Response If "Engine Monitoring" is

programmed to "WARNING" this diagnostic code

Harness for the connector to the coolant level

does not affect engine power.

switch

If "Engine Monitoring" is programmed to "DERATE"

Connector terminals for the switch

or "SHUTDOWN", the vehicle speed is limited to a

maximum of 72 km/h (45 mph), and the power is

Refer to Troubleshooting, "Electrical Connectors

limited. The engine will shut down if conditions exist

- Inspect" for details.

for a long enough period in the SHUTDOWN mode.

B. Perform a 45 N (10 lb) pull test on each of the

Troubleshooting:

wires in the ECM connector that are associated

with the appropriate diagnostic code.

If the vehicle is equipped with the 2-Pin Switch,

proceed with the following steps.

C. Check the ECM connector (allen head screw) for

the proper torque of 6.0 Nm (55 lb in).

2-Pin Switch