DIAGNOSTIC TOOLS & PROCEDURES

Digital Multimeter

The digital multimeter is used to make the required measurements when performing diagnostic testing procedures such as measuring voltage and resistance, checking for short circuits and checking for open circuits.

Since there are varying types of digital multimeters available, this manual does not provide specific instructions. Refer to the instructions provided with your multimeter.

For consistent, successful diagnostic test results, it is essential to understand the following terms:

Voltage (volts) — The electric potential or potential difference, expressed in volts.

Resistance (ohms) — The amount of opposition offered by a component to the passage of a steady, electric current through that component, expressed in ohms.

Continuity (ohms) — Very little or no resistance, indicating that a complete pathway for the current flow exists.

Whenever a diagnostic procedure prompts you to perform a continuity check, be sure to use the continuity feature of your multimeter. Refer to the appropriate multimeter instructions for operating procedures.

Current (amps) — The strength of the flow of electricity, expressed in amps.

Short Circuit (short) — A connection of comparatively low resistance, accidentally or intentionally made, between points on a circuit where the resistance is normally much greater. Open Circuit (open) — Any situation where the normally closed or continuous flow of electricity has been interrupted (e.g., a broken wire in the wiring harness).

Pro-Link 9000

The Pro-Link 9000 is a hand-held device which connects to the serial communication port, located under the dashboard to the left of the steering column. This unit may be used for the following functions: r Display all active faults. r Display all occurrences of inactive faults. r Monitor selected system parameters. r Clear stored fault codes. r Reset low idle speed. r Reprogram customer data.

To use the Pro-Link 9000, follow the instructions provided with the unit.