98 LS400 Clicks but doesnt start
#31
Intermediate
12.14 no load is about 55 % charge at room temperature. Should work just fine in California if battery is OK otherwize. 740A CCA is good.
(Well below the recommended 12.3 V minimum and 70% charge where battery aging accelerates though.)
It is uncommon to kill a battery with one full discharge if it is not left for days but it can loose some of its stamina.
There is probably something else conrtributing like a bad connection to the battery or Starter problem as others have indicated.
If you have a good charger like CTEK ( 60US$ or so ) or simmilar there is often a "recondition button" that helps to mend some of the drain damage.
(Well below the recommended 12.3 V minimum and 70% charge where battery aging accelerates though.)
It is uncommon to kill a battery with one full discharge if it is not left for days but it can loose some of its stamina.
There is probably something else conrtributing like a bad connection to the battery or Starter problem as others have indicated.
If you have a good charger like CTEK ( 60US$ or so ) or simmilar there is often a "recondition button" that helps to mend some of the drain damage.
No one's cars stay above 12.3V that is a pipe dream.
#32
Nope. Do not agree. Not in my LEXUS LS400 . Just checked the details.
I use AGM ( absorbent glass mat) batteries. 70 AH in my both LEXUS LS400
My winter lexus in storage I allowed to warm up idling for 20 minutes yesterday. Sitting for a few months without charger before that.
It measures now 12.72 V on the battery at about 70 F with no load. Means ca 90 % full
My summer LS400 1998 (daily driver) . Measured 12.68 V at 60 Farhenheit with no load. Often driven for a half hour each day at least. Means Slightly below 90 % charge state for a AGM.
I have a voltage meter online at all times in the car in the Phone charger.
What you see is that the battery recharges quite quickly after a start. System voltage goes to around 14 V which means close too fully charged. Takes only a few minutes if you have a good charge to start with. The way it is intended to work and does.
Note: My oldest car battery is now 10 years old (another car) and still ok. More than expected for sure.
If you see 12.3V or less regularly you will be a more frequent customer at the battery store I think.
I use AGM ( absorbent glass mat) batteries. 70 AH in my both LEXUS LS400
My winter lexus in storage I allowed to warm up idling for 20 minutes yesterday. Sitting for a few months without charger before that.
It measures now 12.72 V on the battery at about 70 F with no load. Means ca 90 % full
My summer LS400 1998 (daily driver) . Measured 12.68 V at 60 Farhenheit with no load. Often driven for a half hour each day at least. Means Slightly below 90 % charge state for a AGM.
I have a voltage meter online at all times in the car in the Phone charger.
What you see is that the battery recharges quite quickly after a start. System voltage goes to around 14 V which means close too fully charged. Takes only a few minutes if you have a good charge to start with. The way it is intended to work and does.
Note: My oldest car battery is now 10 years old (another car) and still ok. More than expected for sure.
If you see 12.3V or less regularly you will be a more frequent customer at the battery store I think.
#33
Advanced
Thread Starter
A loud buzz noise from the starter is usually caused by the quick ON/OFF switching of the solenoid. It should be kept ON while the ignition key is turned ON. But when there is a big voltage drop, it turns off. Then the voltage recovers and the solenoid works again. The repetition of this causes the buzzing sound because the solenoid works as if a buzzer. This is caused by different reasons and a layer short of starter motor's winding is one reason. A weak battery or a worn battery terminal is another reason. I worry that your starter motor's winding is short circuited. It can be confirmed by the voltage drop using an oscilloscope at the battery terminal. Sometimes a locked starter motor or a locked engine causes the problem too.
Also should I expect a drop from 12.xx to 10.xx during the voltage drop test - with multimeter?
And I think there is no way to check whether the wires from battery to starter motor is supplying full 12v without removing inlet manifold, right?
#34
Advanced
Thread Starter
Nope. Do not agree. Not in my LEXUS LS400 . Just checked the details.
I use AGM ( absorbent glass mat) batteries. 70 AH in my both LEXUS LS400
My winter lexus in storage I allowed to warm up idling for 20 minutes yesterday. Sitting for a few months without charger before that.
It measures now 12.72 V on the battery at about 70 F with no load. Means ca 90 % full
My summer LS400 1998 (daily driver) . Measured 12.68 V at 60 Farhenheit with no load. Often driven for a half hour each day at least. Means Slightly below 90 % charge state for a AGM.
I have a voltage meter online at all times in the car in the Phone charger.
What you see is that the battery recharges quite quickly after a start. System voltage goes to around 14 V which means close too fully charged. Takes only a few minutes if you have a good charge to start with. The way it is intended to work and does.
Note: My oldest car battery is now 10 years old (another car) and still ok. More than expected for sure.
If you see 12.3V or less regularly you will be a more frequent customer at the battery store I think.
I use AGM ( absorbent glass mat) batteries. 70 AH in my both LEXUS LS400
My winter lexus in storage I allowed to warm up idling for 20 minutes yesterday. Sitting for a few months without charger before that.
It measures now 12.72 V on the battery at about 70 F with no load. Means ca 90 % full
My summer LS400 1998 (daily driver) . Measured 12.68 V at 60 Farhenheit with no load. Often driven for a half hour each day at least. Means Slightly below 90 % charge state for a AGM.
I have a voltage meter online at all times in the car in the Phone charger.
What you see is that the battery recharges quite quickly after a start. System voltage goes to around 14 V which means close too fully charged. Takes only a few minutes if you have a good charge to start with. The way it is intended to work and does.
Note: My oldest car battery is now 10 years old (another car) and still ok. More than expected for sure.
If you see 12.3V or less regularly you will be a more frequent customer at the battery store I think.
#36
Advanced
Thread Starter
#37
Intermediate
#38
Advanced
Thread Starter
Some are impossible to test because of location of starter. And I also think Lexus should be capable enough when it comes to wiring as there are cars from 1992 still surviving at 200k+. But yea give it a try. Some behavior's may not be applicable to ls400 as they're programmed to do that way like the dash would go off during ON position but not for some other cars in those videos but you could use headlamp during ON test to see the drop in secondary.
#39
yes something that draws constant is bad and not unheard of. The regulator function or a weak alternator may be the culprit if voltage is low. I am not sure how the regulator works in the LS. Old school design is to have the regulator on the alternator and quite simple and stupid. Just feeds somthing like 13.6 to 14.2 or so to the battery and nothing more. How fast the battery accepts charge at that voltage decides how fast the battery charges up. More modern arrangement may be to allow the battery to charge up to max 14.4 or so after start and then back down a bit in voltage to ca 13.5 to 13.8 V to prolong the life of the battery. I think I see that the voltage drops a bit after a while on the LS but I do not know how it is done. Some central computer involved ?
#40
Intermediate
To damn complicated... I suppose its like a rats nest trying to figure out what is actually drawing the current. I saw a couple videos that said it can't be done if the battery is sitting at a lower Voltage then it should be. Once I realize my 97 was sitting so low I kinda just brushed it off because it always started.
#41
Moderator
The alternator is nothing to do with the cranking. While cranking the RPM is too low to generate. Other than this, it waits the generation to start some after the cranking is finished due to the function of the gradual excitation power. So we don't need to think any about the alternator while the cranking is going on.
#43
Advanced
Thread Starter
I also found reman starter from Lexus for $168
Part # 28100-50062-84
Part # 28100-50062-84
#44
Advanced
Thread Starter
I managed to remove the intake and now on to the starter motor bolts. Is there anyway I could remove the bolts in a 98 LS400 without removing the coolant bridge and wiring harness?
#45
Lexus Champion
Excellent time to replace gaskets on front and rear coolant bridges...mind the torque specs.
Inspect the condition of knock sensor wiring and replace rubber tubing on bottom of intake manifold-which is sold in bulk at dealer.
Possible side projects:
https://www.clublexus.com/forums/ls-...-manifold.html
https://www.clublexus.com/forums/ls-...crossover.html