
i06011752
Glow
Plug
Starting
Aid
-
Test
This procedure covers the following diagnostic codes:
Table 68
Diagnostic Trouble Codes for the Glow Plug Start Aid Circuit
J1939
Code
Description
Notes
676-5
Engine Glow Plug Relay : Current Below
Normal
The Electronic Control Module (ECM) detects a low current condition in the control circuit
for the Glow plug Control Unit (GCU) for at least 0.7 seconds.
The warning lamp will come on.
676-6
Engine Glow Plug Relay : Current Above
Normal
The ECM detects a high current condition in the control circuit for the GCU for at least
0.2 seconds.
The ECM will attempt to activate the glow plug control unit for a further five attempts after
the diagnostic code becomes active.
The warning lamp will come on.
676-19
Engine Glow Plug Relay : Data Error
The ECM detects one of the following conditions:
The diagnostic signal from the GCU indicates that there is an error in the GCU.
OR
The diagnostic signal from the GCU is invalid.
The warning lamp will come on.
5324-7
Engine Glow Plug 1 : Not Responding
Properly
The ECM detects the following conditions:
The diagnostic signal from the GCU indicates that there is a short in the circuit for the
glow plug for cylinder number 1.
5325-7
Engine Glow Plug 2 : Not Responding
Properly
The ECM detects the following conditions:
The diagnostic signal from the GCU indicates that there is a short in the circuit for the
glow plug for cylinder number 2.
5326-7
Engine Glow Plug 3 : Not Responding
Properly
The ECM detects the following conditions:
The diagnostic signal from the GCU indicates that there is a short in the circuit for the
glow plug for cylinder number 3.
5327-7
Engine Glow Plug 4 : Not Responding
Properly
The ECM detects the following conditions:
The diagnostic signal from the GCU indicates that there is a short in the circuit for the
glow plug for cylinder number 4.
The following background information is related
to this procedure:
The starting aid is used to improve the engine starting
when the engine is cold. With the keyswitch in the ON
position, the Electronic Control Module (ECM) will
monitor the coolant temperature and the engine air
inlet temperature in order to decide if the glow plugs
need to be switched ON. If the glow plugs are
required, then the ECM will activate the glow plug
control unit for a controlled period. While the glow
plug control unit is activated, the glow plug control
unit will supply power to the glow plugs.
Glow plugs are used for temperatures that are below
5° C (41° F).
The GCU transmits a diagnostic signal back to the
engine ECM. If the GCU detects a fault for one of the
glow plugs, a diagnostic code will become active for
that glow plug.
UENR0612
131
This document has been printed from SPI2. NOT FOR RESALE