Hi everyone. My 2009 Vibe GT (Matrix 2.4L) did something(s) odd last night. I was sitting at a red light when the engine started revving on its own, my turn signals stopped working, the airbag light came on, and the digital gear indicator on my dash went blank. The CEL eventually came on on my way home and I found codes P0705 (PRNDL Input-Engine and ECT) and B1660 (some gibberish about the airbag). If that wasn’t bad enough, live data showed my battery voltage at only 12.2 volts while running.
So far, I have checked and adjusted the neutral safety switch (got it lined up in neutral), finally replaced my horrible spark plugs, and even replaced the alternator - none of which made any difference. The most recent work done on the car (besides what I did today) was having the tie rod ends and struts replaced over a month ago. Anyone have any ideas?
Thanks in advance,
Jonas
The charging system needs diagnostics.
Tester
So maybe the trouble codes are red herrings and caused by a charging malfunction? I’ve tried two alternators and both charge the battery a little. As in, the voltage doesn’t steadily go down while running as if running on the battery alone, but both alternators keep the battery around 12 volts at idle.
Did you check if the fusible link between the alternator and the battery has blown?
Tester
2 things . . .
just how old is this battery?
And what condition is the battery connection?
Once you get your charging system figured out and working correctly, if the P0705 is still there…
No, but I will. Fuses are a good place to look for electrical gremlins. Thanks for the diagram!
About 5 months. Connections are clean and tight.
That’s good, but the number of electrical gremlins makes me wonder if this vehicle was ever in a flood.
You’d think! It may have gone through some big puddles, but it was clear day when it just went from perfect to nuts at a stop light.
Number of electrical gremlins? Have there been electrical problems in the past with this vehicle? Charging system/low voltage is a rather common malfunction.
Yes, but never a transmission code, gear indicator going blank, random revving, turn signals failing, and airbag light all at the same time.
I looked closely at the fusible link. None of the wires or innards were separated/burnt.
Not to repeat but if a battery will not take a charge, the battery is faulty. When computers experience low voltage, they go nuts and throw off all kinds of codes.
RESOLVED?
Blown fuse. What made it blow, I don’t know. But my car is tentatively fixed.
One question. Do you think Napa will let me return the alternator I bought yesterday? If not, I do have an old, old alternator I can, at least, return for an $80 core (and have a spare alternator).
1. Time Limit
NAPA Auto Parts allows you to return most merchandise within 90 days of the original purchase. It is important to note that electrical parts are an exception to this policy and must be returned within 30 days.
Tester
Thanks! And thanks for recommending I check the fusible link. It wasn’t specifically that, but you pointed me in the right direction 
A new alternator or used?
It was a “new” remanufactured one. I installed it, but it’s seen very little use and works perfectly fine. I just also have a fairly new denso unit that is still good.
What should the NAPA store do with used parts? Used parts can’t be sold as new.
Non-Returnable Products
Most often, our customers are highly satisfied with their orders, and we consider returns to be a rare but necessary occurrence. That said, there are items for which we are unable to accept returns for any reason beyond a manufacture defect, or an error on our part. These items include:
- Any item not in a new and resellable condition. That includes items without their original packaging, items missing hardware, instructions, or other components that were originally included.
- Items that have been installed or modified in any way. That includes used items, painted items, as well as bent, scratched, or damaged items.