9
votes
Accepted
OBD-II difference between signal ground and chassis ground
You are over thinking things, just connect your devices (OBD & Pi) to a good chassis ground:
The difference between chassis and signal ground is:
Chassis Ground Pin 4: Is exactly that, ...
- 2,785
8
votes
Accepted
'09 Chevy Malibu - No Crank, No Start - Heavy Troubleshooting Already Completed
On GMs now adays the Engine Control Module controls the starter relay. It will look for a park/neutral signal from the range switch and a crank signal from the ignition switch/Body Control Module.
A ...
- 10.7k
7
votes
Accepted
Simplest installation of car-powered car-pc
Most everything external of the ECU is going to be 12vdc (+/-2v). (NOTE: As @juhist points out, more and more cars are supporting 5vdc output to charge handheld devices through USB ports. 5vdc may ...
- 162k
6
votes
'09 Chevy Malibu - No Crank, No Start - Heavy Troubleshooting Already Completed
Looking at the video, it appears to be an electrical problem. It looks like the main power leads are losing their continuity when you turn the key to activate the starter. This issue could be ANYWHERE ...
- 162k
5
votes
Accepted
Installing mobile apps on a car board computer
If I understand you question correctly you want to install your own applications on your on-board computer. To do this you would need extensive reverse engineering and software development knowledge. ...
- 2,785
4
votes
Could the OBD2 connector be used to switch gears?
The commands to read out Speed, RPM and some other sensor data was well as fault codes are standardized for all cars and commonly known. That is, one can "easily" develop some software to read out ...
- 7,057
3
votes
OBD-II difference between signal ground and chassis ground
As Ben stated in the comments, they are both usually grounded to the same point on the chassis. My suggestion to you is to just ground it to the chassis and ignore the #4 & #5 pins altogether. The ...
- 162k
3
votes
Simplest installation of car-powered car-pc
Electronic modules that take car 12V and make 5V are sold at every convenience store, gas station and grocery store in the developed world. Right next to the phone charging cables. They're not even ...
2
votes
How can I determine if a 2015 Nissan Leaf can be monitored/controlled via an app?
I know I'm late to the game here, but just FYI, the S-trimmed LEAF (base trim, available 2013-2017) didn't come with any sort of telematics -- hacked, abandoned, or otherwise. Also the Bluetooth is ...
- 146
2
votes
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How can I determine if a 2015 Nissan Leaf can be monitored/controlled via an app?
Nissan used to have an app called CarWings for the purpose you describe. Problems with it getting hacked caused Nissan to disable that software and move to an app called NissanConnect EV.
...
- 9,005
2
votes
'09 Chevy Malibu - No Crank, No Start - Heavy Troubleshooting Already Completed
Thinking more, you turn the key, massive voltage drop as the starter tries,
1) bad earth to the engine: connect the battery's black wire to a good metal part of the engine, as it is trying to earth ...
- 21
2
votes
Accepted
How important is it to register the new after-market battery in BMW vehicles?
BMW uses a proprietary software to control the charge rate of the AGM batteries in their vehicles. The computer calculates the needed charge rate based on the age and condition of the battery. BMW ...
- 20.1k
2
votes
Simplest installation of car-powered car-pc
Bay of fleas and a DC to DC buck converter plugged into the cigarette lighter controlled by ignition.
Most cigarette lighters go off when the starter is engaged...
- 34.7k
2
votes
Ford Figo not starting immobilizer
The very first thing to do with this is get your battery checked. Then if bad, replace it. Then when you have a working battery, check the charging system. Make sure all battery and charging system ...
- 3,440
2
votes
I took the battery off my car 2006 Honda CR-V
I assume an aftermarket car alarm system.
Factory-installed security systems generally behave better (with some exceptions and I am not aware if your Honda is among the bad exceptions).
It is pretty ...
- 2,385
1
vote
Can I charge my laptop using a simple USB cigarette lighter
Yes, the 100 watt inverter will easily charge your laptop. If your laptop draws less than 100 watts not only can you charge it, you can also use it in your car when you are stopped at a rest area. Net ...
- 3,972
1
vote
Accepted
Can I charge my laptop using a simple USB cigarette lighter
The peak power of your little USB charger is 5*12=60 Watts, and it will get very hot with that. In theory, if your laptop charger's power rating is below that, you may be able to pull this off, but I ...
- 1,086
1
vote
New ECM, car will not crank, VIN is programmed correctly
Your immobilizer is active.
After flashing the replacement ECU with proper VIN and calibrations you need to also program the immobilizer to store the sync codes in the replacement ECU. It needs to be ...
- 3,790
1
vote
BMW E90 2005, 318D to 320 engine question
The 319d engine is simply a 320d but detuned. As far as I know there is a difference in the fuel injectors and the ECU mapping.
319d fuel injector are Bosch #0445110209 while 320d/323d are #...
- 51
1
vote
AC compressor stopped working, electrical/program issue
ECUs are generally supposed to disengage the clutch of a clutch equipped AC compressor when WOT is reached. Something is there to check if the engine is in WOT condition, it may be faulty and be ...
- 958
1
vote
Simplest installation of car-powered car-pc
Coincidentally working on my carpc right now, although it is a mini-ATX box.
I used one of these: http://www.mini-box.com/DCDC-USB-200 - which may be overkill for your application, but provides some ...
- 111
1
vote
Accepted
CASE / CKP relearn without GM Tech II. 09 Chevy Malibu
You need a scantool SnapOn/equivalent or a Tech2 to perform the relearn. AFAIK there is no way to do this without one.
- 10.7k
1
vote
How do I unlock the computer that controls the dash?
There isn't enough info here to give you a solid answer, but from what you have said I think you might find the issue was never the fuel pump or the ECU but something else entirely.
Typically there ...
- 2,879
1
vote
Where should I mount the engine management electronics in a 1993 Ford Mustang?
Is that the EEC-III or EEC-IV or later CPU mounted originally in the passenger kick panel by the door? If so, those computers are inside of cast metal and almost impervious to dirt, etc.
If you want ...
- 227
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