2016 Chevy 4500 "Service Airbag" & No Start???

[GrouchyOldMan]

Many thanks to RV Owner @RockFishon for troubleshooting a pesty electrical problem. I'm just sharing the details.

"I have a 2015 Chevy Express 4500 RV cutaway for a Coachmen Freelander 21QB with a little over 18,000 miles.

Symptom - When trying to start engine, turn key , dash goes dark and nothing happens, the engine does not turn over. Stop turning key and "SERVICE AIRBAG" is displayed and dash chimes 33 times."

Here's the full thread:
https://www.gmtruckclub.com/threads/2015-chevy-express-4500-service-airbag-and-no-start.1455158/

Bottom line: There's a bad solenoid called the Run/Crank relay, and when it goes out your engine won't crank and you may see the "Service Airbag" message on your console.

Solution is to buy a replacement from Napa or Autozone. The problem solenoid is #15 in the fusebox under the hood on the driver's side. You can try replacing it with the A/C relay #40.

Bonus: Here's a diagram of the fuse box layout.
https://www.autogenius.info/wp-content/uploads/2018/01/chevrolet-express-fuse-box-engine-compartment-2011.jpg

I hope this helps someone as much as it saved me an expensive tow job.

Pay it Forward,
-Grouchy

[BruceMc]

Great information! We have a 2016 Sunseeker on the 2015 Chevy 4500 chassis. It currently has nearly 20K miles and I've never had an issue to date.
If this happens in the future, I'll be armed with this nugget, if I can drag it from the dusty crevices of my noggin!
Having the option to swap the AC relay is very useful; many of the relays are the same, so another option may be at hand from a less needed circuit such as the Big-Brother-is-watching(OnStar) circuit! B^)

[GrouchyOldMan]

Thx guys,
I just returned from Napa with two of these relays. $22 each. Also found them in the AmZone for $13, but three week delivery...

Peace Out,
-Grouchy

[FunTwoDrv]

Yep, I've had this relay fail twice in 45K miles!

Gery

[MrWizard]

Info like this is always welcome i hope members b with the same chassis see this info

[MNtundraRet]

Very helpful post.

[Grit_dog]

Thumbs up!