Rick's Free Auto Repair Advice

No AC, Service Power Steering message

AC blows warm and service power steering and drive with care message

GM has issued a service bulletin #PIT5508 to address a situation where the AC blows warm air and you receive a Service Power Steering and Drive With Care Message. The AC blows warm because the AC compressor clutch fuse has blown. The computer may store a C0545 00 / AC compressor Inoperative trouble code or B393B Fuse F60UA or F35UA. The bulletin affects the models listed below:

2015-2016 Cadillac Escalade Models

2014-2016 Chevrolet Silverado 1500

2015- 2016 Chevrolet Suburban, Tahoe

2014-2016 GMC Sierra 1500

2015- 2016 GMC Yukon Models

What causes warm AC and intermittent service power steering and drive with car message

GM has identified a possible wire harness chaffing issue that can cause all these symptoms. Start by checking for an open F60UA or F35UA fuse. If you find an open fuse, the wiring harness is highly suspect.

How to fix AC and power steering issues

1) Remove the under body splash shield so you can examine the wiring harness

2) Examine the wiring harness located below the AC compressor near the power steering rack mount.

AC blows warm, AC compressor won't engage

Locate wiring harness under AC compressor and near steering rack mount

3) GM reports that the wiring harness can rub against the power steering rack mount, causing a rub-through and short condition.



AC blows warm, AC compressur clutch won't engage

Repair wiring insulation cause by chaffing.

If you find a rub through condition, examine the copper wire strands to determine if the wire itself has been damaged. GM reports that most often, just the insulation has been compromised and not the wire itself. If that’s the case, you just need to protect the wire from shorting using heat shrinkable tubing, electrical tape or liquid electrical insulation.


To apply heat shrinkable tubing, remove the wire from the connector and slide the tubing onto the wire before shrinking.

After repairing the damaged insulation, secure the harness so it can’t contact the power steering rack mount—something the GM engineers should have thought of when they designed the vehicle.

Are you listening, you knuckleheads? Seriously, after all these decades of designing cars and trucks you still can’t get this right?

©, 2017 Rick Muscoplat

Posted on by Rick Muscoplat

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