GL320 poor start

[bembo449]

Had a GL320 in for MOT today , it had a funny starting quirk , hope you guys may share your thoughts on it , the car always starts but it displays an almost flat battery way of doing it , reminds me of when cars back in the day had poor live contact onto the starter motor , both batteries are good although ive not stuck the clamp meter on to check any drain , instinct makes me think its not a drain as it can happen when cold or literally 50 secs after the car was shut off , its very strange

 

[Blobcat]

Corroded battery cables? Water damaged and black inside?

 

[ajlsl600]

Bad earth.,corroded,loose poorly. Crimped lugs would be where I check first,assumes batt good sometimes an internal batt connection is not impossible. Rotten cables, unlikely but these days cheaper materials.who knows
Iffy starter relay?

 

[Doug1234]

Sounds like a battery that does not have enough amps , no clout left in it.

 

[bembo449]

But both are new pal

 

[Doug1234]

Still worth the time to drop test just to rule them out