[PRSPlayer]

Greetings,

Just got my 04 CTS-V a few months ago ... love it! Unfortunately right now it has an issue ruining the fun lol

I had the not uncommon "check charging system" while and the car died while driving. Did the basic tests ... battery checks out good. Battery reads battery voltage with the car turned off or running ... sounds like the alternator isn't doing anything. Belt looks fine. Resistance between the alternator body and battery ground is .2 ohms ... seems ok.

That was enough for me, so I went ahead and replaced the alternator ... WRONG ... same symptoms. After reading many threads, I thought for sure it was the alternator connector orange wire ... the PO had replaced broken engine mounts, so it seems to fit the profile. No luck ... the orange wire is reading battery voltage which seems ok. The problem doesn't fit the profile of the grey wire being the issue.

I know I have general grounding issues (don't we all haha). I've had the oil temp sensor problem like so many others. Cleaning up the ground under the hood strut seems to help that. I do still get lots of static on the radio sometimes, and oil temp sensor will still occasionally jump around.

I'm going to try and test the alternator power wire today ... that one's a little harder to get to ... wish I'd checked it when I replaced the alternator haha. Does the 04 V have a fusible link or an alternator fuse? I have a service manual but it is really vague on this point compared to other CTS models.

Any help from the experts here would be so much appreciated!

Cheers,
PRSplayer

 

[darkman]

Have any diagnostic error codes (DTCs) set?

The wiring diagram does show an inline fusible link between the alternator and starter.

I would have the battery stressed tested (one of those that runs for 20-30 minutes) at an auto parts store.

Are there any symptoms other than the "check charging system" indicator?

 

[PRSPlayer]

No DTCs

It did start to throw some other errors after the "check charging system" error. Unfortunately I was trying to wrestle the car off the road into a parking lot as it died ;-) and didn't notice the specifics. I kind of wrote those off as other systems failing due to the lack of power from the primary failure.

I have the battery out again so will definitely have it stress tested.

I guess I need to track down that fusible link ... that wire or the link would have to be it. Does anyone know the path of that wire? Isn't the starter on the passenger side of the motor? Sorry, still getting to know the V.

I guess the other possibility is that Rock Auto sold me a bad alternator argh

Thanks for the help!

 

[darkman]

If the fusible link is blown you will not have continuity on the alternator to starter cable. The service literature indicates that the transmission should be removed to replace that cable, I would check for continuity and/or high resistance before replacing it.

I cannot tell from your posts whether this car starts and runs or not. (If it will not start, the starting system should be addressed first). Assuming that it will start I would hook up a code scanner and check for stored codes.

If the car runs but does not charge the battery the issue could involve the ECM. See attached.

 

[PRSPlayer]

Fantastic information and many thanks! I clearly bought the wrong service manual ... none of that info is in mine.

Back to the task at hand ... yes the V runs fine on battery voltage until the battery dies. If I recharge the battery, the car will run repeating the process. That's how I got the car home when it happened ... took the battery home, charged it, put it back in the car, turned off any unnecessary electrical components, and drove it home.

I assume I need to be able to read Cadillac or GM specific codes? Let me see if I have that extension for my software ... I think I do for my Tahoe.

I'll try that today along with checking continuity on that cable. If there is no continuity on the cable, I hope it's the link and a new one can be spliced in haha if the transmission needs to be pulled, that's a bit beyond my equipment and age adjusted abilities ;-)

Thanks again!

 

[darkman]

I assume I need to be able to read Cadillac or GM specific codes? Let me see if I have that extension for my software ... I think I do for my Tahoe.

I use a $30 OBDII scanner from an auto parts store to check for codes on both my 2005 CTS-V and my 2011 Suburban.

 

[PRSPlayer]

We've had lousy weather the last few days, and now we're heading to Colorado for a week I'll tackle this and report back when we return. Thanks again for the help

 

[Orngfan]

I recently had an issue where the battery was not charging. I did not get a bunch of warning lights, just a check charging system indicator.

I replaced the alternator because the car still had the original one and it was 15+ years old. This did not fix the issue. I diagnosed it to one of the wires being broken for the connector that goes to the alternator. I was able to get a replacement connector with fairly long leads and spliced it in before the break in the original wire.

Image is below of the connector and the 2 leads that are original to the car. The orange wire was damaged causing the no charge issue. It did not appear damaged but the wire was broken inside the insulation. Once the connector/wire was replaced the charging system worked normally.

Hope this helps you diagnose your issue! Good Luck!