Log roller

[sedanman]

I have a 95 Grand Voyager on my lift right now with the trans out, battery still connected power to the starter is isolated. NY just adopted a statewide emmisions testing program that uses the vehicles powertrain control module to verify compliance. C.A.R.B. readiness monitors nust be in the 'ready'staus to pass the test. Disconnecting the battery erases readiness stautus and the monitors have to run on their own in normal opeating conditions. This can take WEEKS and HUNDREDS of miles. Disconnecting the battery erases all the memory. A 2005 model Grand Voyager can have 34 computers yes I said THIRTY FOUR. That's an awful lot of information to be throwing away. I'll tell you how crazy the computerization of cars has become, the key cylinder is no longer connected to an ignition switch, it's a key position sensor and that info is relayed on a bus to a forward control module that completed the requested circuits. The horm pad on many new cars is also wired the same way, there are 5 volt sensor wires replacing a lot of formerly 12 volt high current circuits. THe dash lights no longer dim through a rheo-stat rather a computer switches the totally on and totally off at a duty cycle corosponding to an input from a dimmer switch which is now a potentiometer. A phenomena called 'persistance of vision' takes over and we see an average of tha on time of the lights. Sensors are no hard wired to the control module they are phsically closest to whether that module need the input from the sensor or not. It uses less wire to bus the info to the computer that needs it rather than wire directly. Using computers in this way cut 35 pounds of copper wire out of every single new generation Chryler Corp min-van made 400,000 cars time 35 pounds of copper each.

 

[geofore]

I'm busted on this one because I still disconnect the battery to work on my cars and reset the computers after. Looks like I need to learn some new tricks.

 

[chicken89]

i had a problem with my security system tripping. apparently when i had it installed, they disconnected the battery and never fully tightened it when they reconnected it. it would cause the alarm to cut out the power to the car some of the time, other times the connection to the battery would come lose and the power would go out in the car altogether while driving.
am i saying that you shoudl disconnect the battery?! not always, but if you do, make sure you reconnect it when you are done. caused alot of stress on my wife since she has to transport the kids she babysits for. it cut out on her on the way to work

 

[dayman]

Sedan man,

There are times when you HAVE to disconnect the battery from the car. Do you have any tips on ways to do this without losing the computer memory?

There is a gizmo that is made from a cigarette lighter male end with a 9v battery clip on the other. This is plugged in to send 9v to the radio so that the presets aren't lost. Would something like this work? Could a jumper setup be used to go from cordless tools to the battery terminals?

 

[chicken89]

i am not a mechanic, but what about using a positive end from another battery outside the car? the circut would not be complete, but you will still have power for the other car, and a grounding point from the car you are working on

 

[clearance]

What about driving good old iron?-carb instead of injection for starters, fuel pump on the block with two bolts instead of in the tank. No computers except for h.e.i.. No sensors to sense that you have some cash in your jeans so they can croak. Can't take it in the bush cause it might get scratched type of truck? I always take of the negative cable, takes a few minutes to reset the stations on my tapedeck. Dinosaur in my 80 Chev 4x4, 350 4speed, bush bumpers, sure is great in traffic-people are so polite to me but ignorant to those with nice vehicles.

 

[rb_in_va]

Dinosaur in my 80 Chev 4x4, 350 4speed, bush bumpers, sure is great in traffic-people are so polite to me but ignorant to those with nice vehicles.

Got a pic of the truck?