[hgoettma]

For some reason I have two OBDII units and neither one will communicate with my two Hondas: 2007 Odyssey, 2011 Accord

I understand Honda uses OBDII with CAN protocol. So I made sure both units are compatible with CAN protocol.
First unit: CAS804 Auto Scanner Tool OBD 2 II Trouble Code Reader | eBay

Second unit: OBD2 CANSCAN D900 Engine Code Reader Scanner Free P&P | eBay

Each unit powers up, scans the network protocols and then reports unable to communicate.
It makes no difference if ignition is ON or engine is running.
At this time I have no DTC’s or Engine Trouble light illuminated. Just getting ahead of the curve.

The first unit was tested on a friend’s 2005 Lexus IS300 and it worked. He is now the proud owner a free OBDII reader.
The second unit was tested on a 2009 Hyundai Santa Fe and it worked!

I can’t believe two separate units have the same problem on two cars.
There must be a trick in the Honda to get the CPU to enable communications.
Any ideas?

 

[dvpatel]

There are no tricks. Its the scanners. The cheaper ones are flaky at best. I have tried 2 different scanners on my 2007 and trust me there are NO tricks. They just work if they are correctly compatible with the CAN protocol.

 

[jimfrick38]

I am not sure how this forum works but I can't get my code reader to work on my 08 Odyssey either. Just what does CAN stand for??? I have an 07 Jeep Grand Cherokee with all the bells and whistles and it works, works on a 09 Chevy, and 09 Dodge pick up. Just what is up with Honda??
Auto Zone was able to read it for me ( catalytic converter was not happy) I unhooked battery to clear code then took it out for a drive up to 120 mph and all is fine now. My wife drives like the little old lady she is.

 

[egads]

https://en.wikipedia.org/wiki/CAN_bus

 

[Ump fan]

My 07's CEL has been coming on periodically for a couple years. Autozone usually says its P0456 very small EVAP leak, but has given P0455 medium leak once. I bought a Foseal code scanner that reads CAN, ISO9141, J1850 VPW, J1850 PWM, and KWP2000, and replaced fuel cap. The new cap fixed the problem until my wife closed the new cap on its rubber tether, causing a leak. The CEL has been on a while because the scanner has stopped linking like it had before. The scanner works on my other vehicles. I finally got a 10 mm socket to disconnect the battery to reset the CEL. Now the scanner is connecting! Can anyone explain?