Alright so about 3 weeks ago my well maintained 2013 Tahoe Hybrid with 128k on the clock started throwing the Service Hybrid System message in the cluster. I have driven it a few weeks and the message has become more frequent. No CEL displayed and no stored CEL per my code reader. Auto stop mode still works at lights or while sitting but it seems to kick into the gas motor faster with any throttle input.
I used to be able to roll thru my neighborhood in auto stop or golf cart mode, now it seems to kick in to gas mode ASAP. Mileage seems pretty normal, if down it’s very slight.
I’m going to make an appointment with the dealer this week or next, I will keep this thread updated.
Love my Tahoe but at 128k I’m not certain I want to put $3-5k in her for a battery. We shall see maybe it’s something simple but I’m preparing for the worst.

 

If anyone has had a similar issue please post up.

Oh and first thing I did was check the 12v battery, it was original. I replaced it the day I got the first message and it hasn’t helped.

 

Does CEL turn on prior to engine start?

Have you tried to have codes read at O'Reilly? Their Bosch code readers pick up more than most.

 

I checked this morning, key in the on position all dash lights including CEL come on. Turn it over or start it and it goes away. So the CEL is functional.

 

Did you try O'Reilly?

 

I don’t have one of those local. I will check and see if any parts stores read codes, I know several stopped that service for whatever reason.

My reader shows nothing, fwiw.

 

You already mentioned your reader, hence why I suggested O'Reilly. Most consumer grade OBDII readers can't read most hybrid-specific codes. I've encountered dozens of situations where consumer code readers and AutoZone failed to pull codes. One young, inexperienced individual assumed the dash alerts must be in error and continued to drive the car. About 2 weeks later, one of the battery cells exploded like a gunshot going off in back.

Bosch is big in the professional diagnostics world. I can only conclude their consumer grade stuff benefits from this. They have read codes that ONLY the dealer has been able to pull.

Not sure where "Northern, VA" is, but there's one in Harrisburg and a few in Fredricksburg. If they'll read them for you, it's probably better than a trip to the dealer.

 

I understand 100%, I need a real scan tool. Nearest Orileys is 45 min each way and involves I95, so it’s probably 3 hours each way, lol.
I’ll see if any parts stores near me provide a similar service. Thanks for the help.

 

Understood... though 45 minutes is a typical drive anywhere in the Phoenix metro area... not 3 hours though...

Good luck!

 

I called several places and then a few dealers. I have an appointment next Monday, I will post up after I get the results.

I did not like the general consensus, 300v replacement probability looks high. Ughhhhhhh