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Quick Tip: Chevrolet® Volt Coolant Pump Bleed

Applies To: APOLLO-D8™, APOLLO-D9™, ETHOS® Edge, ETHOS® PRO, ETHOS® Tech, MODIS Edge™, MODIS Ultra™, SOLUS Edge™, SOLUS Legend™, SOLUS Ultra®, TRITON-D8®, VERUS® Edge, VERUS® PRO, ZEUS®

Vehicle: 2014 Chevrolet Volt. Many hybrid vehicles have a separate electric coolant pump that needs to be turned on to help bleed the cooling system. In this Diagnostic Quick Tip, National Field Trainer Jason Gabrenas shows you how to perform a coolant system bleed on a Chevy Volt.



Some hybrid vehicles like this Chevy Volt behind me have an auxiliary electric coolant pump that circulates a coolant throughout both the engine and the battery packs in order to keep them cool.

When you refill that coolant system, a lot of times you have to do a bleed procedure in order to get all the air out of the system. So let's walk through it.

This test is under the Hybrid Powertrain Control Module Number Two. And if we go in there, it's under Functional Tests and is a Special Function and we see we have the Hybrid EV Battery Pack Coolant Pump Bleed Procedure.

Go in there and it says refer to service information when using this test. Connect the required equipment, connect the battery charger to the 12 volt battery; vehicle must remain in service mode during this procedure.

The required equipment that it says, if you look inside the service information, these need to be vacuum filled so you need to use a special vacuum fill coolant filler.

So I’m really just walking you through the procedure here, we don't have any of that hooked up, but just make sure you check your service information for that.

I'll just hit continue to trigger the test. It says to make sure the proper coolant level is in there. And then the procedure will run for about 30 minutes and you can exit the procedure at any time if you wish to do so.

So I'll hit continue. It's going to go in, it's going to start the tests and you can see the numbers are starting to change there.

If I open a couple of graphs, you can see there, it's the percent that it's commanding it on. So I started at 6%, all the way up to 50% and it's cycling through on the pump.

Once the procedure is complete, a final screen is going to come up to tell you that the process is complete.

And once all that's done, you've bled all the air out of the system and the job is done.

Last Updated: August 14, 2020

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