On-Board Diagnostics-II (OBD-II). Questions usually involve scan tools, their use and their compatibility, as well as how to interpret Diagnostic Trouble Codes (DTCs).

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11
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3answers
2k views

Can a vehicle be harmed with bad inputs via an OBD-2 port?

I bought a cheap (sub $10) ELM 327 Bluetooth clone OBD-2 diagnostic adapter on a local "ebay-style" market where the seller specializes in car diagnostics and has several thousand positive reviews ...
10
votes
3answers
82k views

What iPhone/iPad app works best with ELM327 Bluetooth OBD-II reader?

I've found a number of apps for the iPhone/iPad that connect to ODB-II readers via WiFi, but unfortunately that means that it disables 3G and all the benefits of having a 3G device built into my dash. ...
10
votes
3answers
843 views

What to know before buying and OBD-II reader

I read the features to look for in an OBD-II reader, but I am curious if getting one is the right move. I'm just planning to get a cheap one, which is proving to be interesting shopping local. What I ...
10
votes
3answers
483 views

What are good features to look for in an ODB-II reader

I recently took my car in for the engine light. It turned out to be a minor problem (crack in gas cap let water in). It would be nice to have a low-cost ODB-II reader to be able to find out for ...
10
votes
1answer
1k views

How do I find the correct pins in a CAN-BUS connector?

This question might be too technical for this forum, but I'll give it a go. I have a 2012 BMW R1200R motorcycle with CAN-BUS. I'd like to make an Arduino interface to the connector on the bike, but I ...
7
votes
2answers
5k views

Should I replace my own oxygen sensor if i have a Check Engine Light and Code P2195?

My 2003 focus lx 2.0L L4 SOHC ~18,000 miles has had the engine light so i went to autozone to read the code. Autozone obd2 printout says "P2195 lack of heated oxygen sensor- Bank 1 Sensor 1 HO2S11 ...
6
votes
2answers
876 views

Why do we need make-specific cables to read car ECUs?

I find it bizarre that the automotive industry has standardized the use of the OBDII protocol, yet most cars require make-specific cables in order to access the complete set of diagnostics and ...
6
votes
5answers
987 views

Are there any OBD II converters on the market?

I know there are tons of readers and software on the market, but what I really need is something to convert signals of my1970s sensors (fuel level, speed, coolant temp, etc) to OBD compliant signals. ...
6
votes
1answer
2k views

What is supposed to happen when my Subaru's test mode connector is hooked up?

There's an electrical connector under the dash of my 2000 Subaru Forester that is apparently instrumental in the diagnosis of some OBD-II trouble codes. It's a pair of bladed terminals like any other ...
6
votes
1answer
248 views

Does OBD II explicitly or implicitly include forward/reverse information?

From my understanding, OBD II does not directly tell if a car is in forward or reverse gear. I wonder what the best way to derive such information from OBD data if there is any. Following the ...
6
votes
1answer
81 views

ODIS 5.0.6 diagnostic tool : how can I remove an option from a transformed vehicle?

We have a transformed car, a Bentley, which no longer has a motorized sunroof. The blind has also gone. However the car diagnostics exhibits a fault on the related, non-present devices and motors. We ...
5
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3answers
162k views

What is the pin or keycode for ELM327 bluetooth OBDII adapter?

The infamous ELM327 OBDII device came without any paper, just a crappy CD with no document related to the device (only some software and drivers thrown on the CD almost randomly). I tried the ...
5
votes
4answers
3k views

Controlling door locks via CAN bus

I'm trying to figure out how to lock and unlock the doors of a 2010 Toyota RAV4 using the CAN bus via the OBD-II port. I have a microcontroller attached via an CAN controller and a CAN receiver, and ...
5
votes
2answers
239 views

What is the point of a vacuum pump with a fuel injection engine?

I recently got an OBD-II dongle with the Torque Android app, which allows me to read the computer's output in real time. The app will let me drag and drop different gauges on my screen, which works ...
5
votes
4answers
3k views

shop can't connect to onboard diagnostic system?

I've recently moved to California and am trying to get my car registered; they require a smog check (which is possibly actually more of an inspection than the name implies?). I went by a very basic ...
5
votes
1answer
215 views

OBD2 and CAN-bus

Do all vehicles with OBD2 have a CAN-bus? Otherwise, what are the alternative buses used? Are there special versions of the buses for trucks and school-buses than for cars/suv/vans?
4
votes
2answers
51 views

Replacing Cam Position Sensor; any gotchas?

I have a 2007 Nissan Murano. My Check Engine light is telling me that the cam position sensor (bank 1) is bad. I've located the sensors, and they are both readily available and easy to get to. Is ...
4
votes
1answer
825 views

Subaru Forester OBD Scan Codes “P0130” and “P0130 P”

My 2002 Forester Check Engine light is on. I connected an Autel MaxiScan MS300 OBD-II scan tool and got indication for two codes. Browsing through the codes, it reads P0130 and P0130 P. The first one ...
4
votes
2answers
676 views

Reading OBD2 too fast

I'm writing a software to make a telemetry application for my 2001 VW Golf mk4 reading parameters from OBD2 using an ELM327 compatible cable. I succeeded so far. The problem that I have now, is that ...
4
votes
5answers
5k views

Is it worth getting an OBD2 scanning tool?

I have a Opel Corsa 1999 B type. It is giving me problems now. I have read a little bit about OBD2 scanning tools. But don't know if one could help me, or that I am maybe hoping for too much. I ...
4
votes
1answer
584 views

How much battery does an obd bluetooth reader suck?

I'm planning on using an obd bluetooth reader on my car and leaving it plugged in to use apps like dash and torque. It's a daily driver so I'm not that scared of depleting the car's battery, but I ...
4
votes
3answers
8k views

OBD-II reader/scan tool that can also diagnose air bag light

Is there an OBD-II reader/scan tool that can also diagnose air bag warning light? My 2004 Honda Element EX has a red air bag warning light that recently has turned on. The nearest Honda dealer wants ...
4
votes
2answers
714 views

How to view error codes on a speedometer with no OBD reader?

I have a 2000 Dodge Neon and don't have a real OBD reader yet. The other day I started to turn my car on and, before I got to the ignition the speedometer came on with a "p" and a "1684" (the check ...
4
votes
1answer
15k views

'Check Engine' code P0171 System Too Lean - Is it safe to drive?

My 2003 Toyota Corolla's Check Engine Light came on. I read the codes using an OBD code reader and got P0171 - System Too Lean (Bank 1) and P0133 - 02 Circuit Slow Response (Bank 1, Sensor 1). The ...
4
votes
1answer
52 views

Quick Oil Change place overfilled my BMW Z3

Just got this car, a BMW Z3 3.0 from a Tampa dealer and have not even had it 10 days and Check Engine Light came on. I wanted to get the oil changed to full synthetic just in case it wasn't and ...
4
votes
1answer
81 views

How do I get the most out of a “smart” OBDII scanner?

I recently purchased an OBDII scanner that allows me to read and log data using my tablet. How do I get the most out of this device? I am already familiar with simply reading the trouble codes to ...
4
votes
1answer
2k views

Can I use an OBD2 Scan Tool on older GM vehicle?

I can get an adapter that connects my OBD2 scan tool to my 12 pin GM scan tool connection. But will the tool be able to read the codes and tell me anything useful? Or do I need to get a scan tool that ...
4
votes
2answers
2k views

Can an ELM327 OBD-II reader report on anything other than engine trouble codes for a Mini Cooper?

My car (Mini Cooper S) has a service light and tire pressure light on, so I was expecting my new OBD reader to tell me what they were about, but it just says "0 confirmed emissions-related DTCs ...
4
votes
2answers
184 views

Calculating MPG from MAP sensor (or converting MAP data to MAF data)

My 2002 Honda Accord V6 has a Manifold Absolute Pressure sensor (MAP). I understand that this sensor gives out information in pressure units (psi or equivalent). After doing a bit of research, I ...
3
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3answers
2k views

Can OBD-II be used to control the vehicle?

Is the OBD-II port in vehicles only used for reading diagnostic codes or is there some functionality that allows the vehicle (eg. engine revving) to be controlled through OBD-II? Thanks.
3
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2answers
348 views

Writing CAN Messages

I want to know what should I write with the CAN ID to send it to ECU. I am using ELM327 and Raspberry Pi with all connections to OBD-ii. initially for sending general PIDs to the ECU through ELM327 ...
3
votes
3answers
4k views

What should I do about PS0128 “Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)” error code?

I have a Mazda 6 and recently purchased the OBD 2 module and saw the check engine light with the PS0128 Error Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature). I ...
3
votes
3answers
119 views

Failed inspection on because of OBD2 readiness

My 2008 Hyundai failed inspection because the OBD-II system is in a "not ready" state. The mechanic asked if my battery had died recently. It had, after getting an alignment. He suggested driving on ...
3
votes
3answers
2k views

OBD2 to bluetooth adaptor for 2001 Renault?

I have a 2001 Renault Clio 2 1.6 16V (French made) and I'm looking for a OBD2 to bluetooth adaptor to read computer's parameters. There are MANY available with all price ranges, but I'm not sure what ...
3
votes
1answer
60 views

VW Golf IV Possible Engine Misfire

I guess I better start with a few details on the car in question: VW Golf IV 20 valve V5 petrol engine (2.3L) ~80k miles on the clock Now the problem, it feels to me as if the car is down on ...
3
votes
1answer
647 views

How to interface with obd ii elm327?

Do I have to buy this in order to get all the PIDs and the full instruction set for communicating with the car's obd ii interface via an ELM327? I tried looking for some kind of api for the ELM327 ...
3
votes
1answer
162 views

Oxygen sensor PID for 2004 Toyota Camry 4-cyl

My 2004 Toyota Camry with 170k miles is pulling a P0420 code, which I've read can be due to a bad catalytic converter or O2 sensors. I have an OBD-II tool with the DashCommand app on my iPhone. ...
3
votes
2answers
784 views

Mini Cooper P1638 code

I have a 2007 Mini Cooper. It keeps throwing code P1638 on my code reader on these really really cold mornings, and the engine seems to search for idle, reving betwween 500RPM and 1400RPM. The car ...
3
votes
1answer
1k views

What is the OBD-II drive cycle for a 2003 Toyota Corolla?

This site includes a post with the specific drive cycle that resets the OBD-II monitors on several 2000-2002 Toyota vehicles. What does the drive cycle look like for a 2003 Toyota Corolla?
2
votes
2answers
1k views

Accessing Diagnostic Trouble Codes (DTCs) in car

I want to know how can I access DTCs by writing a code and parsing it? I have RaspberryPi and related hardware for communication with the OBD-II of car. I will generate manual faults and then after ...
2
votes
1answer
2k views

What does error code: POO13 mean?

My vehicle: Saturn VUE 2008, 2WD 4Cylider. Checking light is steady on. Read code at auto zone store, POO13. The mileage is only 45K. I have no idea. Thanks for advice.
2
votes
3answers
3k views

How can I check if my 1995 Lancer CC GI has OBD-II

As my title say I want to know if my current car that I just purchased has an ODB-II port. I have looked under the steering wheel and I can see what I think to be a OBD-II connector, but am unsure. ...
2
votes
3answers
792 views

P0420 in a Prius

EDIT #2: I rescanned, looking at the correct data, and found the rear O2 sensor was definitely bouncing up and down with the forward sensor's lambda reading. Since I have looked for leaks and ...
2
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2answers
2k views

Diagnosing “wrench icon” on 2010 Ford Fusion Hybrid: will OBD2 scanner help me?

On my 2010 Ford Fusion Hybrid, I frequently get the yellow "wrench" icon which appears on the LCD screen to the left of the speedometer. On approximately 25%-50% of the trips I take with the car, the ...
2
votes
1answer
242 views

How to add a new transponder / key to a Daihatsu immobiliser

How can I add a new key to a Daihatsu immobiliser? The key I have has a Texas 4C transponder, and is used in the Daihatsu Copen and Daihatsu YRV (to name just two).
2
votes
1answer
631 views

Can I easily replace the Throttle Position Sensor on a 1999 Maxima?

My '99 Maxima's Check Engine light came on recently. I whipped out my OBD-II reader, and pulled off two codes. P0325 (Knock Sensor) and P1705 (TPS) Reading online it appears the knock sensor ...
2
votes
1answer
30 views

what does the highend OBD2 scanner offer?

I just want to clear some misconceptions that i have about the obd2 scanning tools : Is the difference between the high/low-end scanners is the software only? Do the highend use more connection ...
2
votes
1answer
1k views

Citroen Ignition coil problem (P0350 code)

I have a Citroen C4 1.6 petrol (2006) and the other day while I was driving the engine light came on with a message "Depollution system faulty". I connected the OBD-II to my computer to get the error ...
2
votes
1answer
398 views

Read OBD-II Signals Matlab (in real time)

I would like to decode the data obd-ii directly by Matlab (read data directly from reader obd-ii and decimal display in real time.) Should I create a Matlab interface or there is a direct method ...
2
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2answers
785 views

Volkswagen Golf MKV Fault log

I have a folkswagen Golf MKV 2005 model, i used torque to check what the yellow motor sign means, and this is what i received: P2201 - Powertrain NOx Sensor Circuit Range/Performance bank1 P2096 - ...