Computers and Control Systems: Tools and Equipment

The system requires a tachometer, test light, ohmmeter, digital voltmeter with 10 megohms impedance (J-29125A), vacuum gauge and jumper wires for diagnosis. A test light or voltmeter must be used when specified in the procedures. They must NOT be interchanged. For more complete information on the operation of these tools, see the manufacturer's instructions.

Digital Multimeter
(J-39200 or equivalent)





Voltmeter
Measures amount of voltage when connected in parallel to an existing circuit. A digital voltmeter with 10 Meg Ohm input impedance is used because this type of meter will not load down the circuit and result in faulty readings. Some circuits require accurate low voltage readings, and some circuits in the Engine Control Module (ECM) have a very high resistance.

Ammeter
When used as ammeter, this meter also accurately measures extremely low current flow. Refer to meter instructions for more information.
- Selector must be set properly for both function and range. DC is used for most automotive measurements.

Ohmmeter
- Measures resistance of circuit directly in ohms. Refer to meter instructions for more information.
- OL Display in all ranges indicates open circuit.
- Zero display in all ranges indicates a short circuit.
- Intermittent connection in circuit may be indicated by digital reading that will not stabilize on circuit.
- Range Switch
200 Ohms - Reads Ohms directly
2K, 20K, 200 K Ohms - Reads Ohms in thousands
2M and 20 M Ohms - Reads Ohms in millions

Oxygen sensor (O2S) wrench
(J-29533-A)





Used to remove or install the O2S.

Vacuum pump (20 in. hg. minimum)
(J-23738)





Use gauge to monitor manifold engine vacuum and the hand pump to check vacuum sensors, solenoids and valves.

Port fuel injection diagnostic kit
Fuel pressure gauge: J-35957-1
Fuel rail access fitting: J-35957-2




Used to diagnose port fuel injection systems. The kit includes:
- Fuel Pressure Gauge - to check fuel pump pressure and compare injector pressure drop for equal fuel distribution.
- Fuel Rail Access Filling - To easily access fuel line, use this adapter together with the fuel pressure gauge.

Fuel pressure gauge
Used to check and monitor fuel line pressure of port fuel system.

NOTE: Read all instructions thoroughly before preceding. Observe all cautions.

Tachometer





Use inductive trigger signal pickup type to check Engine Speed.

Spark tester
(J-26792)





Use to check available secondary ignition voltage.
Also called an ST125.

Connector test adapter kit





Used to make electrical test connections in current Weather Pack, Metri-Pack and Micro-Pack style terminals.

Circuit tester
(J-34636)





Used to check all relays and solenoids before connecting them to a new Engine Control Module (ECM). Measures the circuit resistance and indicates pass or fail via green or red LED. Amber LED indicates current polarity. Can also be used as a non-powered continuity checker.

Metri-pack terminal remover
(J-35689-A)





Used to remove 150 series Metri-Pack "pull-to-seat" terminals from connectors.

Weather pack terminal remover
(J-28742-A)





Used to remove Terminals from Weather Pack connectors.

Unpowered test light
(J-34142-A)





Used to check wiring for complete circuit and short to ground or voltage.