Vehicle control apparatus

• US 5,012,421 A
• Filed: 04/27/1989
• Issued: 04/30/1991
• Est. Priority Date: 04/28/1986
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Kenki Kabushiki Kaisha
• Inventors: Ishii, Mitsuaki
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): TRANS, VINCENT N
• Application Number:
  US07/344,526
• Time in Patent Office: 733 Days
• Field of Search: 364/431.04, 364/431.05, 364/431.10, 364/431.11, 364/431.06, 123/440, 123/479, 123/480, 123/489
• US Class Current: 701/113
• CPC Class Codes: F02D 41/263 the program execution being modifiable by physical parameters
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: F02D 41/28 Interface circuits

Abstract

A control apparatus for a motor vehicle which can be quickly unit tested during manufacture. Normally, the control apparatus processes signals from various operating condition sensors and applies them to determine the values of control signals to respective controlled elements, wherein there is a delay between the starting of the engine and the use of one of the sensors, namely, the exhaust gas O₂ sensor in determining the value of the respective control signal. To test the apparatus, signals simulating the outputs of at least one of the sensors are set to states which are improbable in acutal operation. Upon detecting such a condition, the control apparatus removes the delay from the starting of the engine and immediately applies all output signals from the sensors to determine their respective control signals.

Claims

1. A control apparatus for a vehicle, which apparatus can be rapidly tested prior to being placed in normal use, comprising:

a plurality of sensors for detecting respective operating conditions at various portions of said vehicle, including an engine of said vehicle;

a plurality of controlled elements operated in response to output signals of said sensors;

time measuring means for measuring a fixed time interval from a predetermined point in time;

state detection means for detecting when an output signal of at least one of said sensors is in a predetermined improbable state which would not occur in normal operation of said control apparatus after said apparatus has been placed in normal use; and

control determination means for reading output information from said sensor and processing said information in accordance with a predetermined procedure, with the output information of at least a first one of said sensors normally having no effect on the respective controlled element for said time interval measured by said time measuring means, said control determined means, upon detection of said improbable state which would not occur in normal operation by said state detection means, applying the output information of said first sensor to control said respective controlled element independently of said time determined by said time measuring means, and prior to the elapse of said time interval.

2. The control apparatus of claim 1, wherein said at least one of said sensors is an O₂ sensor for sensing oxygen content in an exhaust gas of said engine.

3. The control apparatus of claim 1, wherein said state detection means is set when output signals of a plurality of said sensors are in respective improbable states.

4. The control apparatus of claim 3, wherein said improbable states comprise an output of a coolant temperature sensor indicating a maximum coolant temperature, an engine speed sensor indicating a zero engine speed, a throttle position sensor indicating a zero value, an idle switch sensor indicating an off position of an idle switch, and an O₂ sensor for sensing an oxygen content in an exhaust gas of said engine indicating a rich air/fuel mixture.

5. A control apparatus for a vehicle engine, which apparatus can be rapidly tested prior to being placed in normal use, comprising:

a plurality of sensors for detecting vehicle operation conditions, including an oxygen sensor arranged in an exhaust system of said vehicle;

control means for controlling operation of said vehicle engine in response to outputs of said sensors;

timer means for inhibiting said control means from responding to at least the output of said oxygen sensor for a predetermined time following starting of said engine to allow said engine to warm up in normal use; and

means for defeating said timer means during testing of said control apparatus to cause said control means to respond to said output of said oxygen sensor without waiting for said engine to warm up, said means for defeating said timer comprising means for setting a flag upon the occurrence of several sensor outputs which would not occur in normal operation of said control apparatus after said apparatus has been placed in normal use.