reversed jumper cables now it wont start

rbtlen · #1 07-14-2007, 08:19 PM

My battery went dead so when I went to jumpstart my car I screwed up and hooked it up backwards. I have replaced the fusible link, and checked all the fuses. I installed a new battery and installed it correctly but it still won't start. All the dash lights come on as normal but the car won't turn over. What should I look at next?

NikFu S. · #2 07-14-2007, 08:42 PM

What did you use to jump? Another vehicle? Portable charger? Is it ok or dead too?

techy101 · #3 07-14-2007, 10:50 PM

Isn't the system Diode protected???

ensteele · #4 07-15-2007, 12:07 AM

I would check the major fuses or Fuse Link. Good luck and let us know what you find out.

NikFu S. · #5 07-15-2007, 12:09 AM

Don't just check to see if any are broken, check to see if any have melted or burned, and check they are the correct amperage.

Trevor · #6 07-15-2007, 01:04 AM

Quote:

Originally Posted by rbtlen

My battery went dead so when I went to jumpstart my car I screwed up and hooked it up backwards. I have replaced the fusible link, and checked all the fuses. I installed a new battery and installed it correctly but it still won't start. All the dash lights come on as normal but the car won't turn over. What should I look at next?

!. Exactly what did you do? Connect the battery of another car across yours, but with it connected positive to your car negative and negative to positive? 2. Did the dead battery remain connected during the jump start? 3. Was the fusible link replaced because as a result of the jump start, it was blown/melted?

If the fuse link opened as a result of you applying voltage at reversed polarity, this would indicate that something in line past the link, went solidly to ground. However as the dash lights work OK, it would appear that the short has cleared and was short lived. Alternatively that the short was on an independent circuit. If so and it remains, there should be another blown fuse 4. Exactly what does and does not now work within the complete electrical system?

You say that the car won't turn over. 5. Are you sure that the new battery is fully charged and properly connected. If you turn on the head lights while trying to start the car, do the lights stay reasonably bright, thus indicating a good battery and connections?

These are valid questions which can assist with a positive diagnosis.

P.S. Meantime don't panic and expect the very worst as may be suggested.

TomsSVX · #7 07-15-2007, 01:47 AM

I did something similar a couple years ago... I melted my entire underhood fuse box.... Pain in the ass to troubleshoot when the whole thing is melted together inside... Take a peak at yours

Tom

rbtlen · #8 07-15-2007, 08:37 PM

Quote:

Originally Posted by Trevor

!. Exactly what did you do? Connect the battery of another car across yours, but with it connected positive to your car negative and negative to positive? 2. Did the dead battery remain connected during the jump start? 3. Was the fusible link replaced because as a result of the jump start, it was blown/melted?

If the fuse link opened as a result of you applying voltage at reversed polarity, this would indicate that something in line past the link, went solidly to ground. However as the dash lights work OK, it would appear that the short has cleared and was short lived. Alternatively that the short was on an independent circuit. If so and it remains, there should be another blown fuse 4. Exactly what does and does not now work within the complete electrical system?

You say that the car won't turn over. 5. Are you sure that the new battery is fully charged and properly connected. If you turn on the head lights while trying to start the car, do the lights stay reasonably bright, thus indicating a good battery and connections?

These are valid questions which can assist with a positive diagnosis.

P.S. Meantime don't panic and expect the very worst as may be suggested.

I use another battery to jump start. I hooked jump battery pos. to dead battery negative and jump battery neg. to jump battery pos. I have went through the underhood fuse box and checked each side of each fuse and installes a new (subaru) fuseable link. I have checked each side of the in car fuse panel and replaced any fuses that where blown. I installed a brand new battery and it is known good. All the accesories work such as radio, headlights, power windows.

SVXRide · #9 07-15-2007, 09:29 PM

Okay, so now you need to provide more details regarding what you mean by "it won't start". Is the starter solenoid "clicking"? Do you hear the fuel pump running when you turn the key to On? (I'm assuming it still won't turn over)
-Bill

Trevor · #10 07-16-2007, 12:18 AM

I hope I am correct in now assuming that the fuse link was blown due to the mishap, as were other fuses. Can you identify the fuses which you had to replace? This could help a lot.

rbtlen · #11 07-16-2007, 04:17 AM

Quote:

Originally Posted by SVXRide

Okay, so now you need to provide more details regarding what you mean by "it won't start". Is the starter solenoid "clicking"? Do you hear the fuel pump running when you turn the key to On? (I'm assuming it still won't turn over)
-Bill

Fuel pump is coming on, but there is no solenoid "clicking".

SVXRide · #12 07-16-2007, 08:10 AM

Quote:

Originally Posted by rbtlen

Fuel pump is coming on, but there is no solenoid "clicking".

Okay, so you should start looking at the starting circuit, as you're not getting any "juice" to the starter solenoid. Get a voltmeter and check to see that you're getting 12V at the starter.
-Bill

Trevor · #13 07-16-2007, 06:40 PM

I have been trying to ascertain exactly what has happened, but you have been reluctant to answer my specific questions. If you will do so we can be much further ahead with a diagnosis.

The start circuit could not have been affected unless you tried to start the car with the extra battery/car, wrongly connected. This is indeed very likely, but please confirm.

The start circuit is protected by the fusible link as well as fuse SBF 4, which is one of three 45 amp fuses located in the main fuse box. In particular, check this 45 amp fuse and advise what you find.

It is possible that high current, as has been positively indicated as a result of the fusible link melting, has caused damage to the ignition switch start contacts, given that these have been proven to be vulnerable. However it is difficult to accept that this should be the case, as the solenoid winding is not polarity sensitive.

The alternator is involved as a parallel item within the circuit and the included diode network could well be the culprit. If SBF 4 is intact, this will be a likely scenario and you should look for burnt out white coded wiring linking the alternator with the main fuse box.

rbtlen · #14 07-16-2007, 08:37 PM

Quote:

Originally Posted by Trevor

I have been trying to ascertain exactly what has happened, but you have been reluctant to answer my specific questions. If you will do so we can be much further ahead with a diagnosis.

The start circuit could not have been affected unless you tried to start the car with the extra battery/car, wrongly connected. This is indeed very likely, but please confirm.

The start circuit is protected by the fusible link as well as fuse SBF 4, which is one of three 45 amp fuses located in the main fuse box. In particular, check this 45 amp fuse and advise what you find.

It is possible that high current, as has been positively indicated as a result of the fusible link melting, has caused damage to the ignition switch start contacts, given that these have been proven to be vulnerable. However it is difficult to accept that this should be the case, as the solenoid winding is not polarity sensitive.

The alternator is involved as a parallel item within the circuit and the included diode network could well be the culprit. If SBF 4 is intact, this will be a likely scenario and you should look for burnt out white coded wiring linking the alternator with the main fuse box.

I am not sure what questions I havent answered.

I did not try and start the car. I hooked up the jumper cables and smelled the fusible link burning. I will double check again all the fuses

Trevor · #15 07-16-2007, 08:58 PM

Quote:

Originally Posted by rbtlen

I am not sure what questions I havent answered.

I did not try and start the car. I hooked up the jumper cables and smelled the fusible link burning. I will double check again all the fuses

The questions were numbered for easy reference.

What you now state is the most important information you have provided to date. Please now check fuse SFB 4 as requested and advise.

The alternator wiring involves a link in the suspect starting circuit and is very likely to have been burnt out. As advised above, according to the manuals a white coded wire is involved. If burnt out this would break the starter circuit.

Check all alternator wiring and connectors for signs of damage. If nothing is visible, a continuity test is the next step.