Suzuki Ignis Service Manual page 3814

DTC23: No ECM/Immobilizer Control Module Code Transmitted From ECM or
DLC Circuit Opened/Shorted
DTC P1621: No ECM/Immobilizer Control Module Code Transmitted From
Immobilizer Control Module or DLC Circuit Opened/Shorted
1. Immobilizer Control Module
DTC Detecting Condition
When the ignition switch is ON, Immobilizer Control Module requests ECM and ECM requests Immobilizer Con-
trol Module to transmit ECM/Immobilizer Control Module code. If ECM/Immobilizer Control Module code is not
transmitted from ECM or Immobilizer Control Module, Immobilizer Control Module sets DTC23 and ECM sets
DTC P1621.
Troubleshooting
Step
1 Check voltage between Immobilizer Con-
trol Module (1) coupler terminal G19-2
and body ground with ignition switch
turned ON.
Is it 4 – 5V?
2 1) Disconnect ECM coupler with ignition
switch turned OFF.
2) Is there continuity between Immobi-
lizer Control Module coupler (1) termi-
nal G19-2 and serial data link terminal
(G91-10) of ECM coupler? (For posi-
tions of Data link connector terminal
of ECM coupler, refer to "Immobilizer
Control System Wiring Circuit Dia-
gram" in this section.)
1
G19-2 YEL
2. ECM 3. To #9-pin in DLC
Action
YEL G91-10
YEL 3
Yes
Go to Step 2.
Poor G19-2 terminal connection
(Immobilizer Control Module) or Poor
Data link connector terminal connec-
tion (ECM).
If connections are OK, substitute a
known-good ECM or Immobilizer Con-
trol Module and recheck.
See NOTE below.
IMMOBILIZER CONTROL SYSTEM 8G-17
2
No
"YEL" wire short
"YEL" wire between
Immobilizer Control
Module and ECM
open