Problem V2 & Laptop power supply

[johnv]

I'm haveing trouble with V2 and laptop cigerette lighter power supply !

I used an inverter with V1 no problems, but noted the warning not to use an inverter with V2 so bought a proper laptop incar power supply for my HP laptop.
Problem is as soon as I plug it into the laptop, EFI looses comumication with PCM and I have to diconnect and turn everything off for about a minute to get EFI to reconnect

Want to do some auto VE tuneing on a mates car so need a power supply for laptop

[ScarabEpic22]

I run an inverter anyway, I have a 350W Century unit. If my (friends) laptop is fully charged, then I just dont bother at all, but if its not I plug the inverter in for a min and then flash.

[johnv]

I'm a bit loath to try the inverter as I don't want to fry the V2

[eboggs_jkvl]

I've fried 3 connectors (cords) (autotap) by plugging into the cigarette lighter before we figured out the culprit. Now, I either run off the laptop battery OR I have the gadget that takes the 12 v DC and makes it AC (Belkin ACAnywhere model #F5C400-50w). I plug the AC plug of the laptop in and go that way.

[Blacky]

The FlashScan V2 device has protection circuitry that cuts power to the FlashScan unit when an over voltage situation is detected. The circuitry resets after a short time of being unplugged. That is almost certainly what you are seeing.

If you are able to, try measuring the voltage difference between the laptop ground and the vehicle ground. It should be zero volts, if not then you have a ground offset issue and need to find a different power supply that does not produce a ground offset.

Normally when powering a laptop from the vehicle's battery, the power supply is free to set the ground and power voltages at any level so long as the difference between them is the correct voltage for the laptop. For example a laptop that requires 15V may be powered with ground at 9V and power at 24V, a difference of 15V.

However, once you connect FlashScan between the vehicle and the laptop, the ground in the laptop is connected to the ground in the vehicle. That cuases a short circuit across the 9V difference between the two grounds. FlashScan V2 will shut off to prevent damage.

Warning - although FlashScan will usually protect itself, damage caused by incorrect power supply is specifically excluded from the FlashScan warranty.

Regards
Paul


Regards
Paul

I'm haveing trouble with V2 and laptop cigerette lighter power supply !

I used an inverter with V1 no problems, but noted the warning not to use an inverter with V2 so bought a proper laptop incar power supply for my HP laptop.
Problem is as soon as I plug it into the laptop, EFI looses comumication with PCM and I have to diconnect and turn everything off for about a minute to get EFI to reconnect

Want to do some auto VE tuneing on a mates car so need a power supply for laptop

[eboggs_jkvl]

The voltage spread was what was taking out the autotap connectors. Laptops don't care much if it's 24v & 9v or 15v & gnd the v potential is 15v and the laptop is happy. Unfortunately, the 24/9 (and others) combo shoves too much voltage out toward the connector and the A-tap connector went up in a puff of smoke like a flashbulb. If you don't convert the 12v dc from the cigarette lighter to 115v AC and use your AC connection to power the PC, you can fry the connector and you're hosed.

Elmer

[ScarabEpic22]

I've fried 3 connectors (cords) (autotap) by plugging into the cigarette lighter before we figured out the culprit. Now, I either run off the laptop battery OR I have the gadget that takes the 12 v DC and makes it AC (Belkin ACAnywhere model #F5C400-50w). I plug the AC plug of the laptop in and go that way.

Thats an inverter (DC->AC power) bud...

Well, I try to not use my inverter unless I have to, and usually thats only when Im logging for long times. Thanks for the HU, and I will make sure I dont blow it up.

[johnv]

maybe i'll just invest in a second laptop battery, don't want to spend another $180 on a power supply that wont work

How do we measure the voltage offset ?

[ringram]

Im wondering if mr LC-1 has died from a similar experience..
I did note that my inverter has a ground connection which I never bothered to connect. However I have a new laptop with about 2hrs charge. So will use that instead.
Really looking forward to black box logging with v2 now though as 2hrs isnt long really.

[Blacky]

maybe i'll just invest in a second laptop battery, don't want to spend another $180 on a power supply that wont work

The Juice 70 from igo works with FlashScan. Ross (aka GMPX) uses that exact model.
http://www.igo.com/product.asp?sku=3128525 for USD $130 or NZD $185.

How do we measure the voltage offset ?

With the laptop unplugged and switched off, use a DMM with a continuity tester and find a screw or some part of the laptop chassis that is connected to the ground pin of the laptop's power socket. Then when the laptop is fully powered from the vehicle, use the DMM to meassure the voltage difference bewteen the grounded point on the laptop chassis and the vehicle chassis (i.e. vehicle battery -ve).

Regards
Paul