Apparatus is disclosed for storing the circuit conditions existing between a plurality of points established by the conductors of a "known" multiconductor harness and for comparing the circuit conditions existing between a plurality of points established by the conductors of a multiconductor harness to be tested with the circuit conditions of the conductors of the said known multiconductor harness. The apparatus comprises storage means for storing information representative of circuit conditions existing between the plurality of points established by the conductors of the known multiconductor harness, testing means for applying a signal to the points of the harness being examined, detection means responsive to the signal for identifying the existence of circuit conditions between the plurality of points of the harness being examined, transfer means responsive to the detection means for transferring information representative of the circuit conditions of the conductors of the known multiconductor harness to the storage means, comparing means for comparing the circuit conditions existing between the plurality of points as established by the conductors of the known harness with the circuit conditions existing between the plurality of points as established by the conductors of the harness to be tested, signaling means responsive to the comparing means for indicating the results of the operation performed by the comparing means, and control means for selectively operating the transfer means when the conductors of the known harness are connected to the aforementioned points and for selectively operating the comparing means and the signaling means when the conductors of the multiconductor harness to be tested are connected between the aforementioned points.
A signal injecting apparatus which includes a microcontroller for generating a 1024 hertz square wave signal which is supplied through a NAND gate to a field effect transistor. When the transistor is switch on a tank circuit comprising a pair of capacitors and the primary of a signal injector coil starts oscillating and will continue to oscillate when the transistor is switch off. The power level for the signal to the cable is determined by an operator based on the operator inputs from depressing a pair of push button switches. The microcontroller, responsive to the operator inputs from the push button switches, outputs a digital word to a digital-to-analog converter that represents the required power level. The analog output signal from the digital-to-analog converter is supplied to a control loop circuit which adjust the power level by enabling and disabling the NAND gate.
An electronic fuel injection system tester performs a plurality of system integrity tests on individual components and sensors of the system. The tester is plug compatible with the various wiring harness and connectors of the fuel injection system to permit a plurality of integrity tests to be performed either simultaneously or in rapid succession. The tester may be used to test a wide variety of fuel injection systems found in many popular vehicles by virtue of a multiple purpose electronic circuit and front panel template overlays corresponding to each make of vehicle or type of fuel injection system.
A method and apparatus for detecting an improper connection of one or more cables to signal a cable misconnection error. On a board at one end of the cable there is provided a transmit circuit unique to one of the pins or sockets of the connector and at the other end of the cable at an opposite board there is provided a receive circuit that, when the cable is properly connected, receives the signal from the transmit circuit. A misconnection of the cable eliminates the signal from the transmit circuit thus signaling an error at the receive circuit. In addition, semi-dedicated connector positions are also employed so as to assure a detection of a number of different misconnections of the cable, particularly in a multi-cable system.
A system and method for documenting and checking the common connections provided by each wire of a cable between connector terminals located at opposite ends of the cable. The system includes a cable analyzer which is used to generate control information for quickly and reliably verifying standardization of each cable design, an optional printer or other suitable means of documenting the control information, and a binder or other appropriate means for organizing and filing the documentation which contains the control information. The analyzer automatically scans and records the common connections provided by each wire of the cable between the connector terminals at the ends of the cable. The terminal interconnections may then be printed so as to document the cable design for later reference. The analyzer also uses the terminal interconnections to automatically generate and record a unique alphanumeric or numeric code, called a "cable signature," which is also printed as part of the design documentation. Proper cable design can be quickly verified for subsequent cables by using the cable analyzer and the documented design information.
The integrity and connection of cable wires (10-13) extending between two banks of terminals (20-1 to 20-4 and 16-19) are checked for shorts of the wires to ground, to battery wiring between each other and for opens and misconnections or cross-connections of the wires. Unique recognition circuits are provided for controlling, analyzing (circuits 43, 53, 68, 92, 112, 181) and displaying (displays 23, 24, 31 and 32) the test results to accordingly apprise an operator(s) stationed at either or both ends of the cable.
