2008 Escalade - rapid clicking no start

[swathdiver]

12.6-12.4 now that I've cranked it a bunch doing testing for voltage drops

That's getting low but not dead. Can you pull BCM codes yet?

 

[mikez71]

Did you try a new starter relay in the fusebox?

 

[Mordechai]

That's getting low but not dead. Can you pull BCM codes yet?

True but it did the same with a fully charged battery too. And no I haven't tried. Would I get a code for something like this?

 

[Mordechai]

Did you try a new starter relay in the fusebox?

Yeah swapped Relays around with no difference.

 

[swathdiver]

True but it did the same with a fully charged battery too. And no I haven't tried. Would I get a code for something like this?

I don't know but it is important to scan the entire system for codes. Not all codes set a CEL.

Did you watch the video @Fless posted in #14? If you have a corroded line, this could be why not enough voltage is getting to the start to kick the engine over.

 

[j91z28d1]

Here's a video. Also I found a voltage drop! Hooking up one lead to the starter casing and the other end on the battery negative I get what you see in the video. Looks like massive voltage drop. Problem is, i'm not sure where to go from here because testing with one lead on battery negative and the other on the ground that's on the engine that comes from the battery, there's no drop. As far as I know that's the ground the starter/block uses because i'm not seeing anything else. Other than the strap going from the back of the head to the firewall on drivers side which is new. Unless i'm missing one. I know the 5.3 has one hiding behind the PS Pump but the 6.2 doesn't so not sure where to go from here.

https://imgur.com/a/bRBe0cr

that's absolutely low voltage to the starter motor. I've see it for every reason from loose battery terminals on the battery (you shouldn't be about to twist them by hand trying pretty hard) to the starter solenoid itself being bad.


usually it's just a cable or ground issue.

the voltage drop test is from post on the starter to pos battery terminal and neg to neg while cranking. I'm not actually sure what pos at the starter to neg battery terminal tells you.


my quick field test is to grab a old screw driver I don't care about and jump across pos to pos on the stater solenoid and see if it spins the motor over well. if not, look for if it's got good power to it,(cables and battery) if so. I throw a starter at it. I think I've only had that fail once in 20 years of no starts in random equipment. and that was a hidden pos cable ran incorrectly by a past mechanic and it half burned thru the cable by rubbing on the engine block for years. so it didn't have much cable left to carry the load.

 

[Mordechai]

that's absolutely low voltage to the starter motor. I've see it for every reason from loose battery terminals on the battery (you shouldn't be about to twist them by hand trying pretty hard) to the starter solenoid itself being bad.


usually it's just a cable or ground issue.

the voltage drop test is from post on the starter to pos battery terminal and neg to neg while cranking. I'm not actually sure what pos at the starter to neg battery terminal tells you.


my quick field test is to grab a old screw driver I don't care about and jump across pos to pos on the stater solenoid and see if it spins the motor over well. if not, look for if it's got good power to it,(cables and battery) if so. I throw a starter at it. I think I've only had that fail once in 20 years of no starts in random equipment. and that was a hidden pos cable ran incorrectly by a past mechanic and it half burned thru the cable by rubbing on the engine block for years. so it didn't have much cable left to carry the load.

The voltage drop test shows that there's a ground issue. The starter casing is how the starter grounds... There's no voltage drop across the 12v terminals.

 

[j91z28d1]

The voltage drop test shows that there's a ground issue. The starter casing is how the starter grounds... There's no voltage drop across the 12v terminals.

is there a drop from starter housing to neg battery terminal? across pos to neg seeing a drop shows you it's dropping. but not exactly which side is bad. unless I miss read somewhere and you've isolated that it's specifically on the ground side.

is so, check battery neg to engine block and then engine block to starter. fix whichever one it is.

I mean if it turns out to be block to starter isn't making good contact. you can either pull the stater and clean the pad to block contact or just run a ground wire from starter bolt to a clean block bolt.

 

[mikez71]

Is there voltage drop to another part of the engine, like the alt bracket?
(Thinking you tested it to the ground strap, but there could still be a bad connection between strap and motor)

Possible you have a bad new starter?

 

[j91z28d1]

Is there voltage drop to another part of the engine, like the alt bracket?
(Thinking you tested it to the ground strap, but there could still be a bad connection between strap and motor)

the braided ground straps seem to be awful up north too. replacing them with a cable seems like a good idea.

but wouldn't that be block to body ground, more then battery to starter?