6-1-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DATA LINK CONNECTOR (DLC)
DLC (1) is in compliance with SAEJ1962 in its installation posi-
tion, the shape of connector and pin assignment.
K line of ISO 9141 is used for SUZUKI scan tool to communicate
with ECM (PCM), ABS control module and air bag SDM. SUZUKI
serial data line is used for SUZUKI scan tool to communicate with
Immobilizer control module.
Precaution in Diagnosing Trouble
• Don’t disconnect couplers from ECM (PCM), battery cable from battery, ECM (PCM) ground wire harness
from engine or main fuse before confirming diagnostic information (DTC, freeze frame data, etc.) stored in
ECM (PCM) memory. Such disconnection will erase memorized information in ECM (PCM) memory.
• Diagnostic information stored in ECM (PCM) memory can be cleared as well as checked by using SUZUKI
scan tool or generic scan tool. Before using scan tool, read its Operator’s (Instruction) Manual carefully to
have good understanding as to what functions are available and how to use it.
• Priorities for diagnosing troubles (Vehicle without monitor connector)
If two or more diagnostic trouble codes (DTCs) are stored, proceed to the flow table of the DTC which was
detected earliest in the order and follow the instruction in that table.
If no instructions are given, troubleshoot diagnostic trouble codes according to the following priorities.
– Diagnostic trouble codes (DTCs) other than DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too
rich), DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire detected) and DTC P0400 (EGR
flow malfunction)
– DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too rich) and DTC P0400 (EGR flow malfunction)
– DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire detected)
• Be sure to read “PRECAUTIONS FOR ELECTRICAL CIRCUIT SERVICE” in Section 0A before inspection
and observe what is written there.
• ECM (PCM) Replacement
When substituting a known-good ECM (PCM), check for following conditions. Neglecting this check may
cause damage to a known-good ECM (PCM).
– Resistance value of all relays, actuators is as specified respectively.
– MAF sensor, MAP sensor and TP sensor are in good condition and none of power circuits of these sen-
sors is shorted to ground.
2. B+
3. SUZUKI Serial data line
4. K line of ISO 9141
5. Body ground
6. ECM ground
AUTOMATIC TRANSMISSION (4 A/T) 7B1-9
Precaution in Diagnosing Trouble
•Don’t disconnect couplers from PCM (ECM), battery cable
from battery, PCM ground wire harness from engine or main
fuse before checking the diagnosis information (DTC, freeze
frame data, etc.) stored in PCM memory. Such disconnec-
tion will clear memorized information in PCM memory.
•Using SUZUKI scan tool or also generic scan tool for vehicle
without monitor connector, the diagnostic information stored
in PCM memory can be checked and cleared as well. Before
its use, be sure to read Operator’s (Instruction) Manual sup-
plied with it carefully to have good understanding of its func-
tions and usage.
•Priorities for diagnosing troubles
If two or more diagnostic trouble codes (DTCs) are stored,
proceed to the flow table of the DTC which was detected
earliest in the order and follow the instruction in that table.
If no instructions are given, troubleshoot diagnostic trouble
codes according to the following priorities.
–Diagnostic trouble codes (DTCs) other than DTC P0171/
P0172/P0174/P0175 (Fuel system too lean/too rich), DTC
P0300/P0301/P0302/P0303/P0304/P0305/P0306 (Misfire
detected) and DTC P0400 (EGR flow malfunction)
–DTC P0171/P0172/P0174/P0175 (Fuel system too lean/too
rich) and DTC P0400 (EGR flow malfunction)
–DTC P0300/P0301/P0302/P0303/P0304/P0305/P0306
(Misfire detected)
•Be sure to read “PRECAUTIONS FOR ELECTRICAL CIR-
CUIT SERVICE” in Section 0A before inspection and
observe what is written there.
•PCM replacement
When substituting a known-good PCM, check for following
conditions.
Neglecting this check may result in damage to a good PCM.
–All relays and actuators have resistance of specified value.
–MAF sensor, MDP sensor, TP sensor and fuel tank pres-
sure sensor are in good condition. Also, the power circuit of
these sensors is not shorted to the ground.
