Car is my 2008 3.5L EX-L Accord Sedan. Great car but now it has problems.

Day1: Initial problem was the interior blower was not working one morning, then later that day it started working but the VSA/Brake/ABS lights came on. I replaced the blower speed module anyway and while doing that I was able to reset the VSA/Brake/ABS lights and they haven't come on since. Blower seems to work OK.

Day2: Wipers stop working. The wiper relay assembly in the engine bay fuse box buzzes when I try to turn on the wipers. Also, the cabin blower motor stops when i have the wiper stalk in the on position. When I turn the wiper stalk to the off position the cabin blower motor turns back on.

Also noted that the cabin blower motor stop when the radiator fans go to full speed, then the cabin blower motor starts again when the radiator fans go to a lower speed.

I have meticulously checked all three fuse boxes with a test light, checked all fusible links. Pulled the wiper relay assembly and manually activated each relay while checking continuity of all the relay contact. These things all checked out OK.

Codes I have seen: U0122, P1298, b11cf, segment N of the HVAC

 

I don't have a shop manual for the 8th generation Accords. Here is what I found in my 7th generation manual.
U0122: F-CAN Malfunction (VSA-ECM/PCM)
P1298: ELD detected high voltage

What kind of scanner do you have? I'd suggest to clear all the codes and see what code(s) returns.

I'd start with the simple stuff first, clean the battery connections and have the battery and alternator tested to see if they are good. Then troubleshoot the P1298 if that code returns.

 

I am using the 4-9 jumper.

Do you have info regarding the correct voltage range? Please share if you do.

I do have an alternator/system load tester I can clamp on a see how it reacts.

Will do that next.

 

Here is a video on battery/alternator testing

 

I am able to grap the wiper arm and get them moving, sometime. Suppose this is all caused by a wiper motor??

Here are some measurements I just took.

No load at idle measures 14.05vdc at the posts.

Full load, rear defrost, seat heaters, headlights, A/C on, measures 13.3 at idle, 13.89 at 1500rpm.

Measured 0.150vdc drop between alternator + and battery +.

Battery is measuring 12.78vdc at rest.

 

OK, I pulled the plug at the wiper motor. Found ground, speed 1, speed 2 and a sense return-to-home wire.

I found that the ground at this plug measures 2.0vdc to battery post ground.

So i connected a jumper wire from wiper ground to battery ground, when I did this the radiator fan sped up a bit and the interior fan stops falling out.

So, i believe i have a bad ground, somewhere in the system.

Any ideas??

 

I would do the same measurement from wiper ground to the negative battery cable connector. If it is 0, then the battery cable connection is the issue.

You should purchase a pdf of the shop manual for your car on automanualsource.com. It will cost ~$22 and is worth every penny. You can continue your voltage drop test from the wiper motor until you find a point where there is 0 voltage using your volt meter.

 

OK, G301 is the common ground between the blower, wipers and the cooling fan control relay. Check it out, bet it's corroded or loose.