Whilst driving a long distance drive, the dash was showing random different engine light errors. There were two that I observed but was unable to replicate.
- The ABS and E-brake lights were on, and the green “D” (drive gear as opposed to “N”, “S”, or “P”) light was flashing indicating I was driving with the e-brake engaged. I checked the e-brake and pulled it up slightly then down to see if it was engaged. It wasn’t engaged at all. I pulled over as well and exercised the E-brake a few times to see if it would clear. It didn’t. Even when I switched the car from Drive into Park, it still indicated that it was in Drive and the green “D” continued to flash even after pulling over and coming to a complete stop.
- on two occasions, the speedo dropped out completely while the car was moving. This also led to a check engine light coming on (I was unable to get the engine light as I was driving at the time). And the cold engine light came back on. None of these were true as the engine was warm because we’d been driving it for 6 hours at that point on the highway.
- I do use an UltraGuage that is wired and plugs direct into the OBD2 port. I’ve noticed for the past week that sometimes going over bumps will cause the Ultraguage to lose connection to the engine computer despite the connector not coming lose. When the E-brake lights came on, the UltraGuage lost connection and was never able to reconnect, despite the UltraGuage plug being properly connected to the ODB port still.
Also note: I didn’t notice any change in engine performance. ie didn’t hear any changes in how the engine was running, so there was no initial indication that the computer wasn’t getting O2 data or other sensor data to cause it to run too rich/ lean. Once the utraguage did reconnect, all the data it was showing me seemed good. Throttle positions, O2’s etc. They basically tracked what i expected. O2’s changed with acceleration/ deceleration, throttle positions were tracking as well.
My initial thoughts are that there may be a bad circuit or relay, which I plan on checking in the next day or so.
However, I would guess a short in the system or an aging/ dying computer could also be at play.
Any other thoughts of what to check?
+1 to Tester’s comments.
When I had my '92 Honda Accord, a flashing “D” indicated an electronic fault in the transmission. Apparently, Honda continued to use that indicator with later models.
Suggest to repeat the experiment with that gadget removed from the OBD II port. It could be confusing the various car computers, causing all of these symptoms. Honda didn’t test your car with that gadget plugged in while driving, so there’s no telling what the side-effects (if any) it might cause.
Sounds good. I’m thinking something similar. Thus far I’ve had it plugged in over a year without issue but I’m wondering if the device itself is starting to get faulty and is then causing weird data.
Could be. Wouldn’t that throw a code though? I’ve checked on my OBD tester to see if there are any codes and so far there are none.
The Owner’s Manual for my '92 Accord made mention of that flashing “D” warning. Have you looked at your manual to see if it states something to the same effect?
As to codes, my old Accord had OBD-1, so I don’t know if a trans fault would have lit up the CEL.
It’s rare for “the computer” to go bad in a car, even on a 2007.
Agree with removing the Ultra Gauge and seeing if that makes a difference.
Also…how old is your battery? Are you sure the positive and negative battery cables are tight and secure? I know weird stuff can happen sometimes when there’s an electrical issue, such as a dying car battery or loose cable(s).
This would make me even more suspicious of a bad ground (or two) connection. I’d start by looking at the chassis ground(s). Visual inspection looking for corrosion, tightness- tug on the wire, remove and clean all parts and re-install.
Even the battery can have internal issues that could be manifested due to physical jolts. A temporary loss of connection may affect various systems differently, depending on how much bus capacitance they have to hold reserve energy.
Will do. I’ll start checking those. I’ll also confirm the battery. I did some work several months ago where I disconnected the battery. Perhaps I didn’t tighten it all the way and it got a little lose on the long trip.
Good question. I’ll take a look at the sticker on there and check the age. Off the top of my head its no older than 3.5 years since I did replace it since I’ve lived in the state (Moved here 3.5 years ago).
So far I’ve not repeated the issue. I did remove the UltraGuage and haven’t seen the issue. However before I completely removed the guage, I did see it was struggling to connect again. So perhaps its related to this.
Thanks for the suggestions. I’ll see what I can find.
If you live in a warm climate 3.5 years is not an unreasonable battery lifetime especially if it sat on the store shelf for a year.