Vehicle Damage Warnings
ELECTRICAL AND ELECTRONIC1. Always ensure the battery is properly connected to the vehicle prior to attempting to start engine.
2. Don't disconnect the battery when the engine is running.
3. Fully release locks prior to disconnecting connections, ensure connectors are fully seated and all insulators and shields are in place when reinstalling.
4. Never connect or disconnect electrical connections with the ignition switch in the "ON" position unless specifically directed to do so in a test procedure.
5. In order to disable the ignition system, unplug the primary connections only. NEVER disconnect the secondary leads to disable the ignition system.
6. DO NOT use a self powered test lamp to check continuity.
7. DO NOT create any arcing to check the continuity of a circuit.
8. When charging the battery, ensure battery cables are removed.
9. To prevent possible Electrostatic Discharge (ESD) damage to the internal components of the computer module or to other delicate integrated circuits, DO NOT touch these components without the use wrists ground straps which have a minimum resistance of 10.0 Megaohm.
10. When replacing electronic components, disconnect the battery ground.
CAUTION: Before removing battery ground, record stored trouble codes. Computer module memory will be erased when ground cable is removed.
11. When measuring voltage at the control unit harness connector, disconnect harness connector first, then turn ignition "ON" as necessary.
NOTE: Before replacing the computer module use a DVM to check the resistance of each computer controlled relay and solenoid coil. See COMPUTERIZED ENGINE CONTROLS.
12. To prevent deforming of the electronic control unit harness connectors, do not probe terminals directly. Instead, insert a pin from the harness side and perform measurements through pin.
13. Avoid getting water on any of the Fuel or Engine Control System Components.
14. Fuel and Engine Control System wiring should be at least 4.0 inches away from high tension cables.
15. Never pierce ignition leads or insulator boots to connect timing lights or analyzers. Use proper adapters.
16. When removing a spark plug wire, twist the boot one quarter turn and pull on the boot only, never the lead itself.
17. Always use recommended power source in each testing procedure.
18. Never apply battery power to a component unless told to do so in a test procedure.
19. DO NOT try to disassemble the control unit.
20. Never use an auxiliary starting assist device which has a voltage rating above 12.0 volts to start engine.
21. In cases of electrical welding (for instance, spot welding), disconnect the climate control, injection, cruise control, ECU and radio.
22. In case of temperatures above 176°F (80°C), (example: infra-red spray booth), remove all computer modules.
23. The battery produces an explosive gas (hydrogen), avoid creating sparks near battery.
24. Not all SCAN testers are compatible with every system. A SCAN tool that produces faulty readings should NOT be used, and the problem should be reported to the tool manufacturer. Use of a faulty SCAN tool can result in improper diagnosis and unnecessary component replacement. Follow the proper instructions, located in the owners manual, for the specific SCAN tool being used.
ELECTROSTATIC DISCHARGE DAMAGE
Electronic components used in automotive computers are designed to operate at very low voltages (3-5 volts). These components are very fragile to Electrostatic Discharge (ESD). Voltages as low as 12.0 volts can damage computer circuits. By comparison, it takes as much as 4,000 volts of ESD for a person to even feel the electric shock, and there is no way of knowing whether the charge on your body is positive or negative.
There are several ways in which a person can become statically charged. The most common methods of charging are by friction and induction. Friction between organic materials (such as cotton or leather) and synthetics (such as plastic, vinyl, or glass) will generate static charges as great as 25,000 volts. This can happen by simply sliding across a car seat or by wearing a cotton shirt under a coat made of synthetic materials. Charging by induction occurs when a person standing near a highly charged object (strong magnetic field such as a transformer) momentarily touches ground. Static charges are gradually equalized by moisture in the air, but are retained much longer when humidity is low.
USE OF PROPER TOOLS AND TESTING PROCEDURES
Use a Digital Multimeter (DMM) with a minimum 10.0 Megohms input impedance when testing a computer or related components, unless use of an analog meter is specified by a testing procedure. Analog meters have low internal impedance and cause circuit "loading" in low voltage circuits, resulting in inaccurate measurements and possible damage to components. Use of a DMM is necessary to obtain accurate measurements and to avoid damage to low voltage computer circuits and components.
Always follow recommended testing procedures. Never ground or apply voltage to a circuit unless otherwise specified from a given testing procedure. On-board computers provide a regulated constant low voltage source to some circuits, which may require a minimum resistance (impedance) to operate. Directly grounding or applying battery power to these circuits could damage the computer and cause a system failure.
CAUTION: To avoid possible damage to electronic components, observe the following precautions:
1. Discharge any ESD before handling sensitive parts by touching ground or maintaining a ground connection to a bare skin area like the wrist. DO NOT touch these components without the use of wrists ground straps which have a minimum resistance of 10.0 Megaohm.
2. Never touch the PCM connector pins, integrated circuit connector pins, or soldered components on the PCM circuit board.
3. Fully release connector locks prior to disconnecting from harness; ensure connectors are fully seated, and all insulators and shields are in place when reinstalling.
FUEL SYSTEMS
1. DO NOT operate the fuel pump without fuel in the lines.
2. On fuel injected models do not depress the accelerator pedal while trying to start the car.
3. Handle all fuel injection related parts with care as they may easily become damaged.
4. Always use new gaskets or O-rings when installing fuel lines or injectors.
5. Lightly lubricate O-rings and flare connections with gasoline. DO NOT use engine oil, gear lubricant or brake fluid.
6. Relieve the fuel system pressure before servicing the components.
7. After servicing fuel system, check for leaks and correct as needed.
ENGINE AND EXHAUST
1. On vehicles equipped with catalytic converters, the following conditions must be observed:
a. Use only "UNLEADED FUEL."
b. Avoid running out of fuel.
c. In case of poor engine operation (misfiring), avoid driving the vehicle and correct the problem as soon as possible.
d. DO NOT disconnect a spark plug wire with the engine running.
e. Avoid push or pull starting the vehicle.
f. If running on a chassis dynamometer, make sure the catalytic converter is well ventilated.
g. Use caution when working near the catalytic converter to prevent the possibility of burns.
2. DO NOT use silicone based products on an oxygen sensor equipped vehicle to avoid damaging the sensor.
3. When performing a compression test, remove the fuel pump relay. (This prevents fuel from being fed to the injectors).
SUPPLEMENTAL INFLATABLE RESTRAINT (SIR) SYSTEM
All SIR system components, including harness and brackets, must be inspected after an accident. Any SIR components that are damaged or bent must be replaced with new parts even if a deployment did not occur. Never use SIR parts from another vehicle. DO NOT attempt to repair SIR parts; service is by replacement only.