Alternator question

Asked by Timothy Nov 16, 2017 at 08:21 PM about the 2009 Chrysler PT Cruiser Wagon FWD

Question type: Maintenance & Repair

My brand new alternator reads about 0.3 volts when the car is on. There is
also a 12 volt drop from my alternators positive connector to the positive
connector on the battery. Will an alternator put out a bad reading like this if it
is not connected to the battery?

Also my battery dies when sitting for a day or two. Will a bad alternator or
bad connection to the alternator cause the battery to drain just from sitting? It
seems like this shouldn't effect the battery while it's just sitting there. The
battery is brand new.

11 Answers

I would test the alternator at the battery. When the car is running the voltage should read between 13.5 and 14.5 volts more or less. The battery dying may be from lack of charge or from a parasitic battery drain.

1 people found this helpful.

Thanks for the reply. I also checked at the battery. Voltage was 12.8 with car off and 12.4 with car on. However if the wires are bad from the battery to the alternator wouldn't checking at the battery be pointless? Checking at the battery would just tell you the alternator is bad or the wires are bad. I already know the wires are bad so it's going to read bad. I don't know why the voltage drops when the car is on though.

Either the alternator is not charging or like you say maybe there is a wiring problem. Either way you don't have charging. Have the alternator tested at your local auto parts store and inspect the wires and repair them if they are bad like you say. The voltage drops because there is a load on the battery.

Any idea why it would read bad at the alternator? Does the battery have to kick start it for it to read correct voltage?

157,475

If you have a 12 volt voltage drop on the alternator wire then there is a problem. Check the voltage at the battery engine running as suggested above.

I've checked it at the battery as stated above. FOR answered my question of why my alternator is reading bad at the alternator. I wasn't sure if it would put out voltage without being connected to the battery.

59,045

My excellent advise is to replace those known bad wires and then test like normal at the battery.

1 people found this helpful.

I have a 2006 pt cruiser o had my battery check and it's fine every few days my car want start are I can drive it come home that it off and try to restart my car and it's just like it's dead

Your Answer:

PT Cruiser

Looking for a Used PT Cruiser in your area?

CarGurus has 8 nationwide PT Cruiser listings starting at $3,981.

Postal Code:

CarGurus Experts

  • #1
    Kelly Little Ashford
    Reputation
    4,400
  • #2
    Gypsy Rose
    Reputation
    3,290
  • #3
    docwade931
    Reputation
    2,760
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet HHR
4 Great Deals out of 11 listings starting at $2,499
Used Chrysler 300
28 Great Deals out of 519 listings starting at $6,898
Used Volkswagen Beetle
12 Great Deals out of 178 listings starting at $1,495
Used Dodge Dakota
20 listings starting at $3,995
Used Toyota Camry
51 Great Deals out of 1,099 listings starting at $2,500
Used Chrysler Crossfire
14 listings starting at $6,990
Used Chrysler Sebring
35 listings starting at $6,995
Used Ford Mustang
42 Great Deals out of 1,614 listings starting at $8,995
Used Honda Civic
206 Great Deals out of 4,071 listings starting at $2,877
Used Toyota Tacoma
36 Great Deals out of 786 listings starting at $9,975
Used Chrysler Pacifica
25 Great Deals out of 739 listings starting at $15,495
Used Dodge Journey
52 Great Deals out of 936 listings starting at $3,998
Used Chevrolet Corvette
29 Great Deals out of 782 listings starting at $15,900
Used Nissan Versa
11 Great Deals out of 252 listings starting at $3,599

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.