Help! Battery disconnect switch?

[Sept987]

My buddy has a pt cruiser and the dealer quoted hi 800$ to fix a PCM/ECM issue. The issue causes the headlights to stay on at all times--even when the is car turned off.

They have been disconnecting the battery cable each time they exit the car and then reconnecting it each time they drive again. I suggested we try running a master battery disconnect switch to the dash.

After searching this topic online, I noticed several people were weary of bringing the cables inside the cab because of the potential it has to cause fires. I wouldn't want that to happen.

One guy suggested: "Simpler way is to use a 500 amp relay (Ford 7.3/6.0 glow plug relay replacement - sorry can't recall the number) that is located very close to the battery and controlled by a switch in the dash. Simple, cheap, effective - for what the OP *supposedly* wants."

Has anyone run an in-dash disconnect or anything similar. The are just looking for a cheaper alternative to the $800 quote and the effort of manually disconnecting the battery every time they aren't using it.

Thanks guys

 

[JohnVee]

Can you just tap into the headlight harness (or factory HL switch) and use a switch to kill the headlights? Are you positive that nothing else is getting power besides the headlights?

--john

 

[Sept987]

That is a great idea! I'll double check and make sure only the headlights stay on. Thank you! Any other ideas are greatly appreciated.

 

[spotcruiser]

How about getting an ecm from the junkyard?

Edit: Of course you'd need to identify the correct part number, but ecm's can be purchased pretty inexpensively.

http://www.ebay.com/bhp/pt-cruiser-ecu

http://automodulesourceusa.com/Home

 

[Sept987]

So my friend got back to me. Thanks for the help so far.

It is not just the headlights, but the fog lights will stay on as well(I'll look into whether they run on off the same line).

Also, it is the PCM and the TIPM that are bad. The PCM is relatively cheap (thanks spotcruiser) online but the TIPM is still really expensive. http://www.ebay.com/sch/i.html?_odk...5573.m570.l1313&_nkw=pt+cruiser+tipm&_sacat=0

They don't want to put much more money into it. I wonder if these issues will just get worse with time, especially we we just bandaid it with a master battery switch or headlight switch.

Thanks everyone for the help!

 

[spotcruiser]

From the looks of it, that TIPM is just a fuse and relay module. I doubt there is anything there but wiring and terminals. The relays are easily replaced. If there were a problem with the fuse block, it would most likely be a failure of the lights to function, in which case you would be able to pop the back off it and fix the issue. By the symptoms, the lights not turning off, it's either a relay with welded contacts or a faulty ecm/pcm. Has he replaced the light relay?

So my friend got back to me. Thanks for the help so far.

It is not just the headlights, but the fog lights will stay on as well(I'll look into whether they run on off the same line).

Also, it is the PCM and the TIPM that are bad. The PCM is relatively cheap (thanks spotcruiser) online but the TIPM is still really expensive. http://www.ebay.com/sch/i.html?_odk...5573.m570.l1313&_nkw=pt+cruiser+tipm&_sacat=0

They don't want to put much more money into it. I wonder if these issues will just get worse with time, especially we we just bandaid it with a master battery switch or headlight switch.

Thanks everyone for the help!

 

[Sept987]

Spotcruiser- that makes sense. I'll have him try that first. Thanks!

 

[cody c]

Find the wire off the loom that runs to the headlight and fog light relays, then interupt them with another relay, run a wire from ignition power this other relay, it should only work with the key on.

Thats how Id fix it or replace the PCM if it isnt very expensive.