CAUTION
CAUTION |
Airbag system wiring harness is routed near the ECM, main relay and fuel pump relay.
Important | ||
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All airbag system wiring harness
and connectors are colored yellow. Do not use electrical test equipment
on these circuit.
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Be careful not to damage the airbag system wiring harness
when servicing the ECM, TCM, main relay and fuel pump relay.
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Never connect the battery in reverse polarity.
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The ECM
will be destroyed instantly.
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The fuel injector and other part will be damaged in
just a few minutes more.
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Do not disconnect the battery terminals while the engine is running.
A large counter electromotive force will be generated in the generator, and this voltage may damage electronic parts such as ECM, etc.
Before disconnecting the connectors of each sensor and the ECM, be sure to turn OFF the ignition switch.
Poor contact has been identified as a primary cause of this problem. To measure the voltage and/or resistance of individual sensors or all electrical control modules at the harness side connector, use a tapered pin with a diameter of less than 0.64 mm (0.025 in). Do not insert the pin more than 5 mm (0.20 in) into the part.
Before removing the ECM from the located position, disconnect two cables on battery.
Otherwise, the ECM may be damaged.
Important | ||
When replacing the ECM, be careful not to use the wrong spec. ECM to avoid any damage on fuel injection system. |
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The connectors to each sensor in the engine compartment and the harness connectors on the engine side and body side are all designed to be waterproof. However, it is still necessary to take care not to allow water to get into the connectors when washing the vehicle, or when servicing the vehicle on a rainy day.
Use ECM mounting stud bolts at the body side grounding point when measuring voltage and resistance inside the passenger compartment.
(A)
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Stud bolt
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Use engine grounding terminal or engine proper as the grounding point to the body when measuring voltage and resistance in the engine compartment.
Use TCM mounting stud bolts at the body side grounding point when measuring voltage and resistance inside the passenger compartment.
(A)
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Stud bolt
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Every MFI-related part is a precision part. Do not drop them.
Observe the following cautions when installing a radio in MFI equipped models.
Important | ||
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The antenna must be kept as
far apart as possible from the control unit. (The ECM is located under
the steering column, inside of the instrument panel lower trim panel.)
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The antenna feeder must be placed as far apart as possible
from the ECM and MFI harness.
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Carefully adjust the antenna for correct matching.
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When mounting a large power type radio, pay special
attention to the three items above mentioned.
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Incorrect installation of the radio may affect the operation
of the ECM.
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Before disconnecting the fuel hose, disconnect the fuel pump connector and crank the engine for more than five seconds to release pressure in the fuel system. If engine starts during this operation, run it until it stops.
Problems in the electronic-controlled automatic transmission may be caused by failure of the engine, the electronic control system, the transmission proper, or by a combination of these. These three causes must be distinguished clearly when performing diagnostics.
Diagnostics should be conducted by rotating with simple, easy operations and proceeding to complicated, difficult operations. The most important thing in diagnostics is to understand the customer’s complaint, and distinguish between the three causes.
In AT models, do not continue the stall for more than five seconds at a time (from closed throttle, fully open throttle to stall engine speed).
On models with ABS, when performing driving test in jacked-up or lifted-up position, sometimes the warning light may be lit, but this is not a malfunction of the system. The reason for this is the speed difference between the front and rear wheels. After diagnosis of engine control system, perform the ABS memory clearance procedure of self-diagnosis system.