Scania COO DTC 903 Coolant level

COO Coordinator · Scania · 4 variants

Code 903 (decimal). Some diagnostic tools show it in hexadecimal as 0387.

In short

The control unit interprets that the coolant level is too low.

Variant 1

Applies to: COO10 (COO)COO11 (COO)

What does Scania COO fault code 903 mean?

The control unit interprets that the coolant level is too low.

What causes Scania DTC 903?

- The coolant level is too low. - The coolant level sensor circuit in the cable harness has been broken in some other way. - Fault in the coolant level sensor.

How does the system react?

Yellow warning indication for engine coolant level low is displayed.

How to fix Scania COO fault code 903?

  1. Check the coolant level.
  2. Check and, if necessary, clean the coolant level sensor fuse.
  3. Check the cable harness and connections for the coolant level sensor.

Variant 2

Applies to: COO8 (COO)

Detection

The control unit interprets the coolant level as being too low.

Possible cause

- The coolant level is too low. - Open circuit. - Fault in the coolant level sensor. - Fault in cable harness or harness-to-component connector. - Short circuit to earth or break in the circuit if the coordinator is supplying voltage to the coolant level sensor.

How to fix

  1. Check the coolant level.
  2. Check and, if necessary, clean the coolant level sensor fuse.
  3. Check the cable harness and connections for the coolant level sensor.

Variant 3

Applies to: COO9 (COO)

Detection

The control unit interprets the coolant level as being too low.

Possible cause

- Coolant level is too low. - The coolant level sensor fuse has tripped. - The coolant level sensor cable harness circuit has been broken in some other way. - Fault in the coolant level sensor.

How to fix

  1. Check the coolant level.
  2. Check and, if necessary, clean the coolant level sensor fuse.
  3. Check the cable harness and connections for the coolant level sensor.

Variant 4

Applies to: COO8

Detection

The control unit interprets the coolant level as being too low.

Possible cause

- Coolant level is too low. - The coolant level sensor fuse has tripped. - The coolant level sensor cable harness circuit has been broken in some other way. - Fault in the coolant level sensor.

How to fix

  1. Check the coolant level.
  2. Check and, if necessary, clean the coolant level sensor fuse.
  3. Check the cable harness and connections for the coolant level sensor.

This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.

Code 903 in other Scania systems

Compare code 903 in every system →