Interconnect device for detecting whether a vehicle on-board diagnostics (OBD) data port includes circuitry which prevents back feeding of power through the OBD data port
An interconnect device is disclosed for detecting whether an vehicle on-board diagnostics (OBD) data port includes a blocking diode or equivalent. that prevents back feeding of power through the OBD data port. If a diode is detected, the interconnect device alerts the user that the power cannot be back fed through the OBD II port connector. In such a condition, an alternate means is used to preserve the data mentioned above. Specifically, an alternative power supply can be connected directly to the battery cables that will be disconnected from the battery, for example, by way of battery clamps. In this way the alternative power supply is used to preserve the data until a new battery is reconnected to the vehicle battery cables. If a diode is not detected by the interconnect device, the interconnect device displays this fact to the user. The interconnect device includes circuitry for detecting and displaying whether a diode is connected in series with a power pin of the OBD II port connector. In addition, the interconnect device includes an OBD II port connector on one end connected by way of a cable to a connector, such as a cigarette lighter connector or hardwired directly to an alternate power supply.
1. An interconnect device for detecting whether a vehicle electrical system includes a blocking diode or equivalent, the interconnect device comprising:
an OBD II connector for connecting said interconnect device to said vehicle electrical via a vehicle on-board diagnostics (OBD) II port connector;
an alternate power supply connected to said OBD II connector;
a detection circuit, connected to said OBD II connector, for detecting whether the vehicle electrical system includes a blocking diode configured to prevent back feeding of power through the vehicle OBD II port connector;
an indicating device; and
circuitry including a relay for connecting said alternate power supply to said vehicle electrical system if (1) said detection circuit detects that the vehicle electrical system does not contain a blocking diode and (2) the OBD II connector is connected to the vehicle OBD II port connector.
2. The interconnect device as recited in claim 1 , further including a circuit for determining whether said OBD II connector is connected to said vehicle OBD II port connector.
3. The interconnect device as recited in claim 1 , wherein said indicating device is a visual indicating device.
4. The interconnect device as recited in claim 3 , wherein said visual indicating device is an LED.
5. The interconnect device as recited in claim 3 , wherein said visual indicating device is a display.
6. The interconnect device as recited in claim 1 , wherein said indicating device is an aural indicating device.
7. The interconnect device as recited in claim 2 , wherein said circuit determines whether said OBD II connector is connected to said vehicle OBD II port connector based on a voltage measured at said OBD II connector after the OBD II connector connected to said vehicle OBD II port connector.
8. The interconnect device as recited in claim 7 , wherein said connection between said OBD II connector and said vehicle OBD II port connector is assumed if the voltage measured at the OBD II connector is greater than 1.0 volts DC.
9. The interconnect device as recited in claim 1 , wherein said circuitry is configured to prevent said relay from connecting said alternate power supply to said vehicle electrical system unless a voltage at said alternate power supply is greater than a predetermined value.
10. The interconnect device as recited in claim 9 , wherein said predetermined value is 6.0 volts DC.
11. The interconnect device as recited in claim 9 , further including a second indicating device for indicating whether said voltage at said power supply is greater than said predetermined value.
12. An interconnect device for detecting whether a vehicle electrical system includes a blocking diode or equivalent, the interconnect device comprising:
an OBD II connector for connecting said interconnect device to said vehicle electrical system via a vehicle on-board diagnostics (OBD) II port connector;
a connector configured to couple with an alternate power supply and a detection circuit, wherein the detection circuit detects whether the vehicle electrical system includes a blocking diode configured to prevent back feeding of power through the vehicle OBD II port connector;
an indicating device; and
circuitry including a relay for connecting said alternate power supply via said connector to said vehicle electrical system if (1) said detection circuit detects that the vehicle electrical system does not contain a blocking diode and (2) the OBD II connector is connected to the vehicle OBD II port connector.
13. The interconnect device as recited in claim 12 , further including a circuit for checking the connection of said OBD II connector to said vehicle OBD II port connector.
14. The interconnect device as recited in claim 12 , wherein said indicating device is a visual indicating device.
15. The interconnect device as recited in claim 14 , wherein said visual indicating device is an LED.
16. The interconnect device as recited in claim 14 , wherein said visual indicating device is a display.
17. The interconnect device as recited in claim 12 , wherein said indicating device is an aural indicating device.
18. The interconnect device as recited in claim 12 , wherein said circuit for checking the connection between said OBD II connector to said vehicle OBD II port connector is based on the voltage measured at said OBD II connector after it is connected to said vehicle OBD II port connector.
19. The interconnect device as recited in claim 12 , wherein said connection between said OBD II connector to said vehicle OBD II port connector is assumed if the voltage measured at the OBD II connector is greater than 1.0 volts DC.
20. The interconnect device as recited in claim 12 , wherein said circuitry is configured to prevent said relay from connecting said alternate power supply to said vehicle electrical system unless a voltage at said connector connected to said alternate power supply is greater than a predetermined value.
21. The interconnect device as recited in claim 20 , wherein said predetermined value is 6.0 volts DC.
22. The interconnect device as recited in claim 20 , further including an indicating device for indicating whether said voltage at said connector, when connected to said power supply, is greater than said predetermined value.
23. The interconnect device as recited in claim 12 , wherein said connector is a cigarette lighter connector.
24. A method for disconnecting a vehicle battery, the method comprising the steps:
(a) determining, via a detection circuit, whether a vehicle electrical system includes a blocking diode that prevents back feeding of power through a vehicle on-board diagnostics (OBD) II port connector;
(b) connecting an alternate power supply to said vehicle electrical system via the vehicle OBD II port connector if said detection circuit detects that the vehicle electrical system does not contain a blocking diode
(c) indicating, via an indicating device, that the vehicle battery is disconnected from the vehicle electrical system when said alternate power supply is connected to said vehicle electrical system.