2005 Hood Ajar switch
May 16th, 2011, 1:37 PM
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2005 Hood Ajar switch
I've been dealing with a hood ajar message. Finally subscribed to alldata. There is a TSB stating that the switch/sensor design was faulty and a redesigned sensor is available, but only as part of the whole hood latch. I did find out that in Canada, the switch is available separately. But for me shipping would be prohibitive.
I've disassembled the switch and discovered that it has a slider contact and 2 resistors. This switch is not weather proof, a bad design for sure.
When hood is closed, the resistors are connected in series, for a total resistance of about 7k ohms. So I purchased a resistor variety pack at radio shack. I cut the wires off the switch. I soldered a 4.7k ohm and 2.2k ohm resistor in series and then each end of the soldered resistors to the wires originally at the switch. Wrapped in shrink tube and tested. No more hood ajar message. Now my security system and remote start work.
Be warned that this will defeat the purpose of the switch. This means there will be no way the security system will know of hood tampering. This also means that the remote start can be activated with the hood open. So there can be a safety issue. If concerned, just disable remote start in the DIC personalizations.
I've disassembled the switch and discovered that it has a slider contact and 2 resistors. This switch is not weather proof, a bad design for sure.
When hood is closed, the resistors are connected in series, for a total resistance of about 7k ohms. So I purchased a resistor variety pack at radio shack. I cut the wires off the switch. I soldered a 4.7k ohm and 2.2k ohm resistor in series and then each end of the soldered resistors to the wires originally at the switch. Wrapped in shrink tube and tested. No more hood ajar message. Now my security system and remote start work.
Be warned that this will defeat the purpose of the switch. This means there will be no way the security system will know of hood tampering. This also means that the remote start can be activated with the hood open. So there can be a safety issue. If concerned, just disable remote start in the DIC personalizations.
May 16th, 2011, 3:56 PM
#2
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What is the part number for the replacement switch in Canada? Where do you live?
Hard to believe that Canada gets a switch and you don't.
When was the TSB issued? Perhaps a wrecking yard would be a good source for a replacement.
Hard to believe that Canada gets a switch and you don't.
When was the TSB issued? Perhaps a wrecking yard would be a good source for a replacement.
May 16th, 2011, 4:52 PM
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Bulletin No.: 08-08-52-002
Date: February 27, 2008
Subject:
Diagnostic Information for Inoperative Remote Vehicle Start Models:
2005-2008 GM Passenger Cars and Light Duty Trucks (including Saturn)
2005-2008 HUMMER H2 with Remote Keyless Entry RPOs AP3 or AP8
Information on Hood Latch Switches
One of the many components involved in the Remote Vehicle Starting System is the Hood Latch Switch. The state of this switch is checked by the BCM during a remote vehicle start request and the component must function properly in order for the vehicle to commence a remote start event. During the infancy of this option (RPO AP3/AP8) parts return analysis showed a significantly shorter than expected component life for the Hood Latch Switch shared across many different GM vehicles.
The switches currently being factory installed, and sent as service replacement parts, are vastly improved in design and suitably robust. Most hood latch switches currently returned under warranty are analyzed and determined to have no trouble found (NTF). It is understandable and desirable that technicians gain familiarity with the vehicles they service on a daily basis, however it is required that technicians follow Strategy Based Diagnostics before replacing this switch.
Important: The ONLY way to repair or replace a hood latch switch is to replace the LATCH ASSEMBLY. The switch CANNOT be serviced separately from the latch and is NOT AVAILABLE from GMSPO. Any effort to remove the switch from the latch will permanently damage the switch and void the warranty coverage of that part.
Date: February 27, 2008
Subject:
Diagnostic Information for Inoperative Remote Vehicle Start Models:
2005-2008 GM Passenger Cars and Light Duty Trucks (including Saturn)
2005-2008 HUMMER H2 with Remote Keyless Entry RPOs AP3 or AP8
Information on Hood Latch Switches
One of the many components involved in the Remote Vehicle Starting System is the Hood Latch Switch. The state of this switch is checked by the BCM during a remote vehicle start request and the component must function properly in order for the vehicle to commence a remote start event. During the infancy of this option (RPO AP3/AP8) parts return analysis showed a significantly shorter than expected component life for the Hood Latch Switch shared across many different GM vehicles.
The switches currently being factory installed, and sent as service replacement parts, are vastly improved in design and suitably robust. Most hood latch switches currently returned under warranty are analyzed and determined to have no trouble found (NTF). It is understandable and desirable that technicians gain familiarity with the vehicles they service on a daily basis, however it is required that technicians follow Strategy Based Diagnostics before replacing this switch.
Important: The ONLY way to repair or replace a hood latch switch is to replace the LATCH ASSEMBLY. The switch CANNOT be serviced separately from the latch and is NOT AVAILABLE from GMSPO. Any effort to remove the switch from the latch will permanently damage the switch and void the warranty coverage of that part.
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