Remote vs immobilizer vs battery Issues
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Joined: Feb 2002
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From: Portland, OR
Remote vs immobilizer vs battery Issues
I'll do my best to describe the issues and hope you can help w/ 97 993 C4 cab:
#1 if i don't start my car at least weekly--the battery is weak at best. Right now battery is dead. (Battery < 6 mo old)
#2 I am no longer able to elicit any response from my key remote to lock/unlock car despite frequent A23 battery changes.
#3 I am unable to jump start the car because the key remote had only enough energy to lock the car but not unlock it.
#4 where should I start? replace the R61 relay? I am not a mechanic--obviously--just want to be smart about how to get out of this mess before going to a dealership/local mechanic.
#5 what could be wrong in the "recieving unit"?
#6 I only have one key/remote--Appreciate any advice you may have
"miserable in Pinehurst"
#1 if i don't start my car at least weekly--the battery is weak at best. Right now battery is dead. (Battery < 6 mo old)
#2 I am no longer able to elicit any response from my key remote to lock/unlock car despite frequent A23 battery changes.
#3 I am unable to jump start the car because the key remote had only enough energy to lock the car but not unlock it.
#4 where should I start? replace the R61 relay? I am not a mechanic--obviously--just want to be smart about how to get out of this mess before going to a dealership/local mechanic.
#5 what could be wrong in the "recieving unit"?
#6 I only have one key/remote--Appreciate any advice you may have
"miserable in Pinehurst"
Racer
Joined: Oct 2005
Posts: 374
Likes: 2
From: New Jersey
You need to get a Battery Tender Plus from amazon.com.
If your car battery is dead, nothing is getting unlocked with the remote and you'll have to manually unlock it. I'm not sure what will happen once you get get juice in the battery as typically the alarm goes off when you open the door with the key. I guess at that point, you can press the remote to disarm the alarm.
My father's towncar had his battery dead, I took my Batter Tender Plus over to his and let it charge over night. Next day it was fine. I charged it all week just to be safe and ordered him a charger from amazon.com for 45.95 no tax and free shipping.
If your car battery is dead, nothing is getting unlocked with the remote and you'll have to manually unlock it. I'm not sure what will happen once you get get juice in the battery as typically the alarm goes off when you open the door with the key. I guess at that point, you can press the remote to disarm the alarm.
My father's towncar had his battery dead, I took my Batter Tender Plus over to his and let it charge over night. Next day it was fine. I charged it all week just to be safe and ordered him a charger from amazon.com for 45.95 no tax and free shipping.
Rennlist Member
Joined: Oct 2003
Posts: 7,210
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From: Nova Scotia
I suspect that you either have a bad battery, alternator not charging correctly, or a low amperage draw short to ground.
If the battery has gone absolutely flat, charge it up fully and cart it off to NAPA, etc for a freeby CCA test ( cold cranking amps). That will confirm whether the battery stays or is replaced. Later, when the car is started, measure the voltage at the battery terminals with a DVM ..... ~14V should be present with motor running = a good alternator. ( 12.3 - 12.6 = good battery, engine off)
Most of these chronic 'flat battery' issues are neither of the above: it is usually a switch or relay contacts that are partially closed and draining to ground: if the DVM has a reasonable ammeter capability, place it in series with the +ve battery terminal. A normal current draw is in the order of 20-30ma ( eg - dash clock, radio memory) with all doors closed. If the draw is much higher than that, start pulling fuses one by one until the draining circuit is identified. This is not a lot of fun .....
If the battery has gone absolutely flat, charge it up fully and cart it off to NAPA, etc for a freeby CCA test ( cold cranking amps). That will confirm whether the battery stays or is replaced. Later, when the car is started, measure the voltage at the battery terminals with a DVM ..... ~14V should be present with motor running = a good alternator. ( 12.3 - 12.6 = good battery, engine off)
Most of these chronic 'flat battery' issues are neither of the above: it is usually a switch or relay contacts that are partially closed and draining to ground: if the DVM has a reasonable ammeter capability, place it in series with the +ve battery terminal. A normal current draw is in the order of 20-30ma ( eg - dash clock, radio memory) with all doors closed. If the draw is much higher than that, start pulling fuses one by one until the draining circuit is identified. This is not a lot of fun .....
Last edited by Garth S; May 10, 2007 at 07:16 AM.
Rennlist Member
Joined: Jun 2005
Posts: 3,033
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From: Sandy, UT/Fish Haven, ID
Get a battery kill switch. Not a resolution but a battery saver if your car sits for awhile and an additional security device.
As far as the immobilizer--take it to a stereo shop that knows alarms. Im going to have mine reworked because I cant figure out how to overide the alarm-even with the switch in the glove box. The PO put a couple of alarms/window and moon roof roll up and down combo that I dont quite understand in full detail. When my battery died in my immobilizer, I was dead in the water one time and couldnt figure it out hence the reason why I carry a spare immobilzer and a few batteries.
As far as the immobilizer--take it to a stereo shop that knows alarms. Im going to have mine reworked because I cant figure out how to overide the alarm-even with the switch in the glove box. The PO put a couple of alarms/window and moon roof roll up and down combo that I dont quite understand in full detail. When my battery died in my immobilizer, I was dead in the water one time and couldnt figure it out hence the reason why I carry a spare immobilzer and a few batteries.
Instructor
Joined: Oct 2005
Posts: 246
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From: Napa weekdays,Fort Bragg other days
also, check to see if you can hear the quiet whine like something is running with your ear below and near the glove box after you turn the car off. the air temp unit is a common leaker of current @ about 400milliamps/hr. had similar prob in my 97 c2 cab. i believe Interstate makes the best battery for the best price. david schiff
Track Day
Joined: Jul 2006
Posts: 21
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97' TT and same problem.....drive car once per week...Battery almost dead after a week....read a lot of posts and I will go ahead and replace my ground strap to be sure....causes a lot of weird issues....bought a battery charger with a built-in "minder". Alt. tested and was fine...It is just what you have to do to keep everything in check....just make sure you press down on the hood latch to turn off lights and make sure you pull the handle inside before you close the hood...
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First of all it seems like you have an energy "leak" somewhere..You should get this sorted out first (could be ground strap or whatever stated in the posts above). I can't give any good advice on this since I'm not an electrician: I'm not even close to it..
However, as a more preventive measure you might want to consider the following mod (which I am tempted to persue myself: The idea is that of a built in battery tender with an external connector that is hidden somewhere under the front bumper cover or inside the front wheelwell. There are battery tenders that are not very big or heavy so you should be able to hide it somewhere in the area where the spare tire sits.
Pros and cons? Well, the only Con I can think of is weight. But then again, its marginal and it sits in the right place (low and front). The major Pro is that it increases the lifetime of your battery remarkably. AND its very easy to use. However I assume that you have electricity somewhere near where you park your car at home. Just plug the cord in when you get home and you will always have your battery at optimal power level. Or if not every day than just plug it in when you know that you won't be using the car for a week or so. Just my 0,02$. Good luck
!
However, as a more preventive measure you might want to consider the following mod (which I am tempted to persue myself: The idea is that of a built in battery tender with an external connector that is hidden somewhere under the front bumper cover or inside the front wheelwell. There are battery tenders that are not very big or heavy so you should be able to hide it somewhere in the area where the spare tire sits.
Pros and cons? Well, the only Con I can think of is weight. But then again, its marginal and it sits in the right place (low and front). The major Pro is that it increases the lifetime of your battery remarkably. AND its very easy to use. However I assume that you have electricity somewhere near where you park your car at home. Just plug the cord in when you get home and you will always have your battery at optimal power level. Or if not every day than just plug it in when you know that you won't be using the car for a week or so. Just my 0,02$. Good luck
!
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Thread Starter
Rennlist Member
Joined: Feb 2002
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From: Portland, OR
Well--took the battery in and recharged it (good battery) and had voltage meter reading--~13. So I take that to mean the alternator is not a good one and charging the battery. You know I've owned this car since Feb '02 and have had the alternator replaced at least once and alternator belt changed in '02, '03' 04 and '06. The alt belt pulley was replaced in '06 as well. What is the life expectancy of an alternator and belt? The alternator , when replaced was provided under my extended warranty and beleive it was a "refurbished" Bosch part. Should I fell as frustrated as I am with these repeated issues--??
Rennlist Member
Joined: Oct 2003
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From: Nova Scotia
Originally Posted by C9RN
Well--took the battery in and recharged it (good battery) and had voltage meter reading--~13. So I take that to mean the alternator is not a good one and charging the battery. You know I've owned this car since Feb '02 and have had the alternator replaced at least once and alternator belt changed in '02, '03' 04 and '06. The alt belt pulley was replaced in '06 as well. What is the life expectancy of an alternator and belt? The alternator , when replaced was provided under my extended warranty and beleive it was a "refurbished" Bosch part. Should I fell as frustrated as I am with these repeated issues--??
If the voltage measured at the battery terminals is unchanged after starting the engine, clearly the alternator is not charging ( there should be an ~ +1.5v increase); however, if that is the case, the dash should light up like a Xmas tree ... Trust that an accurate ( eg digital) meter was used, for it is the moderately small differences that count: sorry, but "13v" doesn't really tell me anything.
- what is the voltage at the battery with engine off? - and when running?
The alternator failing to provide the required 115 Amp output at 14v can be as simple as low belt tension - ie., slippage : also, not turning due to a seized bearing would toss/destroy the rearward 760mm belt .... quite obvious
Another common reason is worn brushes or a regulator that has blown .... or the mechanic did not make good connections with the three wires attached to the alt. Less likely is a blown power diode inside the alt.If the belt tension is OK, then I would pull the alt and check it out: I recently pulled the 68K mile alt when doing a RS pulley/hub conversion ( to single belt drive), and pulled the reg/brush assembly - to find the brushes quite worn. After swapping in a spare 'fresh' alt, it was a mere 5 min to install a new regulator & brushes .... a mere $20 generic 'Bosch' as used by the Service Shops. That alt will be ready for another 60K+ miles. My point being that it is reasonably simple to do if you are equipped for DIY tasks.
