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?

 

[mikez71]

He said he had no drop to the ground strap (block side), but does on the starter case. ? If I'm reading right..

 

[j91z28d1]

He said he had no drop to the ground strap (block side), but does on the starter case. ? If I'm reading right..

yeah I was a bit confused with that too. unless where it mounts to the block is very rusty from salty roads between the starter and the block. I don't think I've ever seen a starter not make a good ground to the block. but I have never had to deal with road salt.

 

[Mordechai]

UPDATE! I hooked a 1 gauge jumper cable from the battery ground to the firewall ground and it started right up. I then disconnected it and it's constantly starting normally now but I still have about 1.25v of voltage drop at the firewall ground when starting. I'm thinking of adding a ground cable directly from the battery to the firewall. Is that a good idea or no? Thank you

https://imgur.com/a/nY6noMl

 

[Fless]

Before adding anything I'd probably first replace the engine-to-body ground with a new cable (rear of left head to the firewall). I'd also remove and clean the battery ground at the block, wherever that is on yours.

 

[Mordechai]

Before adding anything I'd probably first replace the engine-to-body ground with a new cable (rear of left head to the firewall). I'd also remove and clean the battery ground at the block, wherever that is on yours.

I already added a new oem ground strap from firewall to the head but didn't make a difference. Added it to a different location and doubled it up with factory old ground as people seem to recommend around here. And there's no direct to block ground that I know of on these.

 

[Mordechai]

Or maybe adding a ground strap from firewall to alt/power steering bracket? I know some of em came with that.

 

[Fless]

I already added a new oem ground strap from firewall to the head but didn't make a difference. Added it to a different location and doubled it up with factory old ground as people seem to recommend around here. And there's no direct to block ground that I know of on these. View attachment 448551

Is the new one connected to an exhaust manifold bolt?

 

[Doubeleive]

Or maybe adding a ground strap from firewall to alt/power steering bracket? I know some of em came with that.

your main battery ground should go here on the passenger side front end of the head, there will be a smaller lead off of the same cable that feeds down to the top of the frame on the passenger side part way up under the radiator support.

I personally also added a large ground from the alternator bracket to the frame on the drivers side

 

[Doubeleive]

voltage drop to the starter "typically" indicates a bad starter cable, just food for thought but if a ground fixes it then great found the problem.

 

[j91z28d1]

voltage drop to the starter "typically" indicates a bad starter cable, just food for thought but if a ground fixes it then great found the problem.

I was thinking ground for the starter going thru the fire wall might not be great. sounds like the starter is getting it's ground from that small wire off the terminal to bumper ground, thru the body and back to the starter. instead of from the thick ground from battery directly to block.