so I give up on all my TPMS sensors going on all day like feris wheel and going to jag dealer to get ripped.

before I go - I went to a Pep Boys to have them check battery/starter/alternator.
(remember this is -6 month old jag which is now constantly going me "turn on car or audio will be shut down-this goes on WHEN CAR IS RUNNING AND NO AUDIO ON .

PEP BOYS RUNS COMPUTERIZED LOAD TESTS -


RESULTS

A) BATTERY RATED 820/MINE WAS PUTTING OUT 750 VOLTAGE 12.2.
NEEDS RECHARGE
COMPUTER ALSO SPITS OUT
"BATTERY IS GOOD BUT THE STATE OF CHARGE IS LOW. CHECK FOR PROPER SYSTEM OUTPUT FOR ECESIVE KEY OFF DRAW"

WHICH MEANS- WHILE I AM SLEEPING 15 FLOORS ABOVE THIS CAR SOMETHING ELECTRICAL IS RUNNING - AND I LISTENED FOR FUEL PUMP ETC


B) STARTER TEST - CRANKING NORMAL VOLTAGE 11,020


C) ALTERNATOR- "NO PROBLEMS"
NO LOAD 14.350
LOADED 14.230

IN MY HEAD- ALLLLLLLL THE PROBLEMS IM HAVING WITH THE TPMS GOING OFF ALL THE TIME =YESTERDAY "GEARBOX WARNING"" ARE ALL TIED TO THE BATTERY

BUT JAG WILL WANT TO IMMEDIATELY THROW A TPMS MODULE AT ME - THEY SOLD ME THE BATTERY= I WOULD LIKLE TO ASK THEM TO EITHER SWAP IT OUT OR PUT ONE THATS USED BUT FUNCTIONAL IN IN FOR A WEEK

THEY WONT

 

Hello jwmciti,

Sounds like you may have a draw, yes. There are ways to check for draw on today's newer vehicles with CAN-BUS communication; you can always try that first before going to the dealer.

After letting your car's ECU go into "sleep" mode (15 minutes is typically sufficient), you can check each and every fuse at the Central Junction Box, under the hood, and in the boot. Using a DMM on the mV setting, you can chart the draw using a simple formula.

My suggestion is this: leave passenger door and hood open and let the car sit for about 15 minutes until the ECU goes to sleep. Using your DMM, set the meter to mV (auto is fine) and for each fuse, put one lead to each "tit" on the top of the fuse - you will see two "holes" on the top of each fuse where you can stick your DMM lead tip. For each and every fuse, write down (1) the fuse number, (2) the amperage rating, and (3) the draw in mV.

Most fuses will read 0.0-0.1 mV across the top of the two t*ts. When you find a reading significantly higher than that (I have seen 20-30 mV) - make note of that fuse and what it controls. There's a draw on that fuse. I have a chart attached that crosses the mV draw with the fuse's amp rating. By using the chart, you can see what the actual draw is to the vehicle.

When you find one (or more) with a significant mV reading, check to see if there are any remedies to eliminate that draw. Again make sure that the car is "asleep" AND make sure your keys are nowhere nearby - the interior lights will be off and the car should be silent.

I'm not sure if I can explain this any better, but there may be a reference somewhere out there on the interwebz that speaks to the procedure more eloquently than I just did.

Again, try to find the source of your draw yourself before you assume you are going to get bent over at the dealer. Many times, the technicians at these dealerships have the know-how and tools to test these cars correctly; there are just some tools that only dealers have to read our cars. It is what it is sometimes and you have to have some faith when you have exhausted all of YOUR options first.

I hope this helps you take one more crack at it before sending to the dealer.
Thanks.

Erik Quick
MECP Certified Installer
Owner, Mobile AVC

 

Sorry, attached the doc now.

 

Erik,
That's an interesting idea, you're using the fuse as a shunt resistor and measuring the voltage drop across it.
Trouble is (as you see from your chart) it depends on the rating of the fuse. The big ones will have an extremely low resistance so this test will be very insensitive.
I honestly think the 'old fashioned' way - disconnect the -ve lead and put a meter on Amps range between it and the negative battery post is better suited. The drain should drop to 50 ish mA when everything goes to sleep.

 

Just a thought, have your car had the software upgrade to rectify the excessive draw because it dies not go completely to sleep?

 

I'm going to ask abt the software upgrade - and a print out of all that was done to car since day one

i still say these all all related to install of new battery 6 months ago

 

You might want to check out this video:

 

this is unreal. so of course jag says my toms needs new module and receiver.
the advisor never brought my Pep Boys load test to tech.
i go back to (sneak) to the area show the tech the report he said "after a 50 mile drive this was the reading"
then the advisor basically throws me out

end of story is
a) he says shot receiver and module- has to be ordered
i say how much module - he says $400 ish + 300 install and program
i show his Meridian same part # etc $168
and receiver - i forget

then he says bring in the parts and u pay for the labor

I'm posting this again in new thread