2006 IS350: Won't start or even attempt to crank when hot unless jumped
11-27-19, 10:12 PM
#16
To diagnose:
Sitting voltage should be 12.7 across battery. What is it?
In the ideal world everyone has a Fluke 87 with Min/Max values and for example can impose a load and see the Minimum voltage. The voltage the system dropped too while cranking.
That said, place the meter leads across the battery and the meter at the windscreen and see what the cold start drop it. It's pretty normal to see a 1 volt drop during system start with engine cranking.
Record:
Engine off battery voltage:
Accessory on battery voltage: Note - lights and everything in the cabin OFF!!!
Minimum Battery voltage seen while cranking:
Repeat above when HOT!!!! post it.
Additional info to gather to reduce T/S time:.
With alligator clips or a helper:
Place the meter in Volts. Place one probe on Negative Battery post and the other end on the engine block. While Cranking the engine cold, report the voltage. Ideal loss is Zero. Repeat when hot. If this Number is greater than say 0.2V, you have a bad engine ground cable.
Repeat this same test on the Positive battery post (NOT THE LEAD BUT THE BATTERY POST) to the Starter Positive battery lead. What are the cold vs how voltages?
Next step: Is the solenoid getting the current it needs to operate the starter? Meter is set to Voltage. Connect Meter to the Battery Negative terminal. Find the Small solenoid terminal next to the starter. Connect meter there. Expect battery voltage. If lower than battery voltage, something is wrong.
This sounds like a lot of info to gather but it will isolate where the problem is/isn't.
Sitting voltage should be 12.7 across battery. What is it?
In the ideal world everyone has a Fluke 87 with Min/Max values and for example can impose a load and see the Minimum voltage. The voltage the system dropped too while cranking.
That said, place the meter leads across the battery and the meter at the windscreen and see what the cold start drop it. It's pretty normal to see a 1 volt drop during system start with engine cranking.
Record:
Engine off battery voltage:
Accessory on battery voltage: Note - lights and everything in the cabin OFF!!!
Minimum Battery voltage seen while cranking:
Repeat above when HOT!!!! post it.
Additional info to gather to reduce T/S time:.
With alligator clips or a helper:
Place the meter in Volts. Place one probe on Negative Battery post and the other end on the engine block. While Cranking the engine cold, report the voltage. Ideal loss is Zero. Repeat when hot. If this Number is greater than say 0.2V, you have a bad engine ground cable.
Repeat this same test on the Positive battery post (NOT THE LEAD BUT THE BATTERY POST) to the Starter Positive battery lead. What are the cold vs how voltages?
Next step: Is the solenoid getting the current it needs to operate the starter? Meter is set to Voltage. Connect Meter to the Battery Negative terminal. Find the Small solenoid terminal next to the starter. Connect meter there. Expect battery voltage. If lower than battery voltage, something is wrong.
This sounds like a lot of info to gather but it will isolate where the problem is/isn't.
08-15-20, 12:06 PM
#17
Driver
Thread Starter
To diagnose:
Sitting voltage should be 12.7 across battery. What is it?
In the ideal world everyone has a Fluke 87 with Min/Max values and for example can impose a load and see the Minimum voltage. The voltage the system dropped too while cranking.
That said, place the meter leads across the battery and the meter at the windscreen and see what the cold start drop it. It's pretty normal to see a 1 volt drop during system start with engine cranking.
Record:
Engine off battery voltage:
Accessory on battery voltage: Note - lights and everything in the cabin OFF!!!
Minimum Battery voltage seen while cranking:
Repeat above when HOT!!!! post it.
Additional info to gather to reduce T/S time:.
With alligator clips or a helper:
Place the meter in Volts. Place one probe on Negative Battery post and the other end on the engine block. While Cranking the engine cold, report the voltage. Ideal loss is Zero. Repeat when hot. If this Number is greater than say 0.2V, you have a bad engine ground cable.
Repeat this same test on the Positive battery post (NOT THE LEAD BUT THE BATTERY POST) to the Starter Positive battery lead. What are the cold vs how voltages?
Next step: Is the solenoid getting the current it needs to operate the starter? Meter is set to Voltage. Connect Meter to the Battery Negative terminal. Find the Small solenoid terminal next to the starter. Connect meter there. Expect battery voltage. If lower than battery voltage, something is wrong.
This sounds like a lot of info to gather but it will isolate where the problem is/isn't.
Sitting voltage should be 12.7 across battery. What is it?
In the ideal world everyone has a Fluke 87 with Min/Max values and for example can impose a load and see the Minimum voltage. The voltage the system dropped too while cranking.
That said, place the meter leads across the battery and the meter at the windscreen and see what the cold start drop it. It's pretty normal to see a 1 volt drop during system start with engine cranking.
Record:
Engine off battery voltage:
Accessory on battery voltage: Note - lights and everything in the cabin OFF!!!
Minimum Battery voltage seen while cranking:
Repeat above when HOT!!!! post it.
Additional info to gather to reduce T/S time:.
With alligator clips or a helper:
Place the meter in Volts. Place one probe on Negative Battery post and the other end on the engine block. While Cranking the engine cold, report the voltage. Ideal loss is Zero. Repeat when hot. If this Number is greater than say 0.2V, you have a bad engine ground cable.
Repeat this same test on the Positive battery post (NOT THE LEAD BUT THE BATTERY POST) to the Starter Positive battery lead. What are the cold vs how voltages?
Next step: Is the solenoid getting the current it needs to operate the starter? Meter is set to Voltage. Connect Meter to the Battery Negative terminal. Find the Small solenoid terminal next to the starter. Connect meter there. Expect battery voltage. If lower than battery voltage, something is wrong.
This sounds like a lot of info to gather but it will isolate where the problem is/isn't.
what do you mean by windscreen
08-16-20, 10:52 AM
#19
Driver
Thread Starter
I thought we had the problem fixed but we kind of werent giving it an opportunity to happen again. the car sat for awhile while we were out of state and when we got back it happened a few times so if we went somewhere in it we would leave it on and just lock the doors or one person would just stay in it. but it was getting ridiculous my gf would be leaving the car on for hours at s time and i said screw that. i had the dealership and 3 other mechanics look at it to no avail. then i finally got my multi meter hooked it up and from the alternator to battery tested resistance which should of been 0 or 1 at most and it would say 0 or 1 but then flash all crazy and go back 1 or 0 so i said screw it went bought few things and redid the ground again after 2 people already did things to it... but i went did the right way. i tested again and it heldsteady at 1
08-18-20, 07:09 PM
#20
Because its connected to the battery, current is flowing to keep things alive.
Like I said before, do a voltage test with the leads in the same place. There should be zero volts or NO energy loss in the cables.
For example: place a lead on the negative battery post. Place a lead on the engine block near the ground. Measure DC volts at a low setting like millivolts.
What is the value when Starting the Engine and when running with the AC on?
Like I said before, do a voltage test with the leads in the same place. There should be zero volts or NO energy loss in the cables.
For example: place a lead on the negative battery post. Place a lead on the engine block near the ground. Measure DC volts at a low setting like millivolts.
What is the value when Starting the Engine and when running with the AC on?
06-14-22, 06:20 PM
#21
3rd Gear
Join Date: Sep 2014
Location: Texas
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Help!
There was recently a thread exactly like this.
Do nothing else but this; take one side of your jumper cable and attach it to the engine block. Take the other end and attach it to the battery negative post. When hot, does it start?
If yes, your ground cable is bad. Likely at the terminal to the battery.
Look for my posts on this topic. Good info.
Do nothing else but this; take one side of your jumper cable and attach it to the engine block. Take the other end and attach it to the battery negative post. When hot, does it start?
If yes, your ground cable is bad. Likely at the terminal to the battery.
Look for my posts on this topic. Good info.
06-14-22, 10:59 PM
#22
Advanced
If I were to guess you either have a frame grounding issue or a ground cable issue.
Thread
Thread Starter
Forum
Replies
Last Post
mandyfig
IS - 2nd Gen (2006-2013)
11
09-03-13 02:06 PM
sherlock
LS - 1st and 2nd Gen (1990-2000)
21
01-14-10 09:45 AM