No start issue still.

Post by **subzerocarfanatic** » 03 Jun 2020, 22:46

I finally got the NOCO G3500 battery charger/maintainer for AGM batteries, it was under charged when it arrived by a bit,it is fully charged now and so is the interstate battery i had been using,it will be my test battery for working on the car.
I tried using a test light to find my short to ground problem if i had one, Vida Dice still will not communicate with the ETM nor the ECM, I tried running other test,it said the battery voltage was 10.59 but by meter is was 1260, that was before i done a slow trickle charge on the new AGM battery I just bought.I cliped one end of test light to positive battery cable, which is not connected to positive battery post, then the test light tip on battery positive post, the light should not be lighting up unless i'm missing something, I pulled all the fuses and relays in the main fuse box to try and find what is causing my issue but after going through them all the light remained on the entire time. I am doing my best to look through the wiring diagrams i have found online,it's a task for me.

yanga001 · Post by **yanga001** » 04 Jun 2020, 11:59

The low voltage meter might indicate the undercharged battery is just gone. I had a similar issue where a battery lost all its capacity even though it could maintain a charge and hold 12.6 Volts. I verified this by metering it while running a small 12 V inverter. The voltage drastically dropped to around 10 volts. Does the car crank or click when you turn the key? Also, pm'd you full diagrams.

Post by **subzerocarfanatic** » 04 Jun 2020, 12:15

I have a brand new battery I just bought,still does the same.

yanga001 · Post by **yanga001** » 04 Jun 2020, 12:22

subzerocarfanatic wrote: 03 Jun 2020, 22:46 I cliped one end of test light to positive battery cable, which is not connected to positive battery post, then the test light tip on battery positive post, the light should not be lighting up unless i'm missing something,

Was the negative post connected? You would still be completing a circuit in that case and the light would come up. If its like an incandescent light then polarity would not mater hence it would still come up. If you have a meter with a continuity test then maybe try that. Start close to the source and work your way down eliminating components.

Post by **kranz** » 10 Jun 2020, 08:56

subzerocarfanatic wrote: 04 Jun 2020, 12:15 I have a brand new battery I just bought,still does the same.

Subzero, please PM me.

kranz

Post by **abscate** » 10 Jun 2020, 13:12

You can't use old school techniques on new cars.

A Volvo can take 30 minutes to go to rest state, and even then, you have battery and ECU memory drawing current, and thus lighting up your positive terminal series test light.

Post by **subzerocarfanatic** » 10 Jun 2020, 13:49

abscate wrote: 10 Jun 2020, 13:12 You can't use old school techniques on new cars.

A Volvo can take 30 minutes to go to rest state, and even then, you have battery and ECU memory drawing current, and thus lighting up your positive terminal series test light.

I have started going through wiring harness again, unplugged the ETM and removed it, i plugged it back in while it was out of the car and it starts now, weird.

Post by **scot850** » 10 Jun 2020, 16:03

Sometime there is a build up of oxidisation on the contacts of the ECM and TCM. I had a similar issue with a TCM and after being removed and re-seated after a clean using Wurth contact cleaner (that is what local dealer uses), issue disappeared.

Hopefully that is all it was with your car too.

Well done,

Neil.