Service manual

G420F(FE) Service Manual Chapter 9. Advanced Diagnostics 297
Table 2. Diagnostic Fault Codes (Flash Codes) cont’d.
DFC PROBABLE FAULT FAULT ACTION *
CORRECTIVE ACTION FIRST
CHECK
437
EST7_Short
EST7 output shorted high or low,
EST7 signal shorted to ground or
power or defective spark module
None N/A
438
EST8_Short
EST8 output shorted high or low,
EST8 signal shorted to ground or
power or defective spark module
None N/A
461
(26)
ETC_Sticking
Electronic Throttle Control is
sticking. This can occur if the
throttle plate (butterfly valve)
inside the throttle bore is sticking.
The plate sticking can be due to
some type of obstruction, a loose
throttle plate, or worn components
shaft bearings. NOTE: The throttle
assembly is not a serviceable item
and can only be repaired by
replacing the DV-EV throttle
assembly
(1)TurnOnMil
(2) EngineShutdown
(3)CutThrottle
Check for debris or obstructions
inside the throttle body
Check throttle-plate shaft for bearing
wear
Check the ETC driver wiring for an
open circuit
SECM Pin A17 to ETC + Pin 1
SECM Pin A18 to ETC - Pin 4
Check the ETC internal motor drive
by disconnecting the throttle
connector and measuring the motor
drive resistance at the throttle
TPS Pin 1 (+DRIVER) to
Pin 4 (-DRIVER) ~3.0-4.0
471
ETC_Open_Fault
Electronic Throttle Control Driver
has failed, normally set if either of
the ETC driver signals have
opened or become disconnected,
electronic throttle or SECM is
defective.
None
Check the ETC driver wiring for an
open circuit SECM Pin A17 to ETC +
Pin 1
SECM Pin A18 to ETC - Pin 4 Check
the ETC internal motor drive by
disconnecting the throttle connector
and measuring the motor drive
resistance at the throttle
TPS Pin 1 (+DRIVER) to Pin 4 (-
DRIVER) ~3.0-4.0
481
(28)
ETCSpringTest
Electronic Throttle Control Driver
has failed, normally set if either of
the ETC driver signals have
opened or become disconnected,
electronic throttle or SECM is
defective.
Electronic Throttle Control Spring
Return Test has failed. The SECM
will perform a safety test of the
throttle return spring following
engine shutdown. If this spring
has become weak the throttle will
fail the test and set the fault.
NOTE: The throttle assembly is
not a serviceable item and can
only be repaired by replacing the
DV-EV throttle assembly.
(1) TurnOnMil
(2) EngineShutdown
Perform throttle spring test by
cycling the ignition key and re-check
for fault
(*) Fault actions shown are default values specified by the OEM.