| ID | Status | Date | Year | Make | Model | Transmission Type | A/C Controls | Public/Private |
|---|---|---|---|---|---|---|---|---|
| #13329 | Closed | 2003 | Chevy | Trailblazer | public |
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Seems I am not getting signal to the low pressure switch: |
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I would start by checking to make sure there are no a/c or coolant related codes stored in the PCM. If you have access to a scan tool that will communicate withe the PCM and HVAC modules I would look at data related to the a/c. Without a scan tool I would use a voltmeter to see if there is any voltage on the dark blue wire at the clutch cycling switch. The switch has to be unplugged to make this test and the ignition and a/c have to be on. I would also try switching the a/c clutch relay with another known good one. There should be multiples of that relay in the underhood fuse box. |
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Thanks Sparky I will have my buddy check the blue wire on the clutch cycling switch again but for as I know we checked that and no signal is coming off that wire we even tried forcing the clutch to kick in by jumping the plug with no luck. |
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Jumping out the wires at the clutch cycling switch will only work if everything else is okay. In addition to listening for the a/c clutch to engage you should also listen for changes in the engine rpms as it is jumped. If the rpms change with the jumping of the wires the circuit is likely to be okay and the problem will be between the relay and the compressor. You may want to have one hand on the relay as the switch is jumpered so you can feel if it clicks. Keep in mind that the voltage may be 5 volts. The compressor clutch does not have to be functional in order for the clutch cycling switch circuits to work. How many miles of your Trailblazer? If the mileage is high you might want to consider excessive clutch air gap. I do recommend using a scan tool for diagnosing this system.
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