Honda CR-Z Hybrid Car Forums banner
1 - 19 of 19 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter · #1 ·
Hello all,


I've been trying to diagnose my CR-Z's problem. It's a 2011, CVT trans, only 55K miles, mostly babied all its life. The IMA, Check IMA System, battery light and engine light came on during a 45 minute drive home one night a couple weeks ago.

The next morning I checked and the underhood 12V battery was dead. I checked the codes, my scanner showed only "1634" and 15 amp fuse number 53 was blown.

I installed a new battery, replaced the fuse, erased the code, cleared the check engine light and the car seemed to right itself. The only thing I noticed that seemed out of the ordinary was that the car didn't seem to charge the hybrid battery pack as easily as it always had when I took my foot off the gas. I drove the car 5 or 6 times without any other issues.

Two days ago it was 30*F, I started the car, the IMA light came on immediately. Fuse 53 was blown again. Scanner showed 1634 and 1448. Underhood battery showed 12.7 volts and very good cranking power. I changed the fuse, as soon as I turn the ignition to "ON", the fuse blows - I tried this multiple times. {Side note, sorry to jump ahead on the timeline here - I once accidentally started the car with the rear IPU fan disconnected and the fuse did NOT blow}

Today I removed the rear interior body panels to access the hybrid battery fan. I successfully conducted the steps outlined below up to step number 16 - "Turn the battery module switch off". I don't know where that switch is. The MCM connector, PCU lid, etc..I don't know what / where these are-- can someone please give me some direction where I can learn about these things and how to safely work on them?

I've watched hours of YouTube videos and Googled all of these terms but I'm obviously wasting my time with that method of learning. If nothing else, I'd really like to just properly test the IPU module fan to see if it works as it should or see if I should start looking elsewhere to find the problem(s). I don't want to just order a new fan and see if that fixes the problem, I want to properly troubleshoot the issue and (hopefully) fix the problem right out the the gate. If that means ordering a new fan, not a problem, I'm happy to do it but I don't want to just start buying and changing parts to see if I get lucky. I never get lucky.

Hopefully this time, I'll get lucky with this community's knowledge and help - thanks in advance for any help or direction you can give me with this,

Dave


Font Parallel Document Number


Font Material property Parallel Document Monochrome

Font Material property Parallel Document Number


Font Number Document Screenshot
 

·
Registered
Joined
·
1,939 Posts
I successfully conducted the steps outlined below up to step number 16 - "Turn the battery module switch off". I don't know where that switch is. The MCM connector, PCU lid, etc..I don't know what / where these are-- can someone please give me some direction where I can learn about these things and how to safely work on them?
On the battery in the trunk, there's a trapezoidal-shaped approx-palm-sized metal cover held on by a single 10mm bolt. Remove bolt and cover, the main switch to the high voltage system is there. Wait 5 minutes after switching off for capacitors to discharge before continuing.

Its page 12-4 in the Factory Service Manual for pictures. To turn back on you have to press the little circular switch next to the main switch, its a sort of lock.
 

·
Registered
Joined
·
905 Posts
I would not waste your time with diagnosis, especially if you don't have an HDS or OBDIIC&C to turn the fan on/off to see if it is working. .

It's a very common issue and almost certainly a fan failure so just repair or replace it.

The fact fuses are blowing clearly indicates one or more of the fan drive internal mosfets are shorted.

If it was a simple break in a wire or failure of the MCM to command the fan on/off then fuses would not blow. (Reverse logic)
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #6 ·
Understood, thank you very much.
So there is no way to bench test the fan without the HDS or OBDIIC&C devices you referenced? I watched your video :

but I figure there must be more to a thorough bench test than just that?

Lastly, do you guys have a preferred source for replacement fans ? (I'm near Detroit, Michigan).

Thank you all very much for your help and guidance with this!!
 

·
Registered
Joined
·
1,939 Posts
Lastly, do you guys have a preferred source for replacement fans ? (I'm near Detroit, Michigan).
For parts that have no aftermarket/third party manufacturer you can go used or new OEM. Used parts Redline is really good for CR-Z stuff but it doesn't look like they have an IMA fan right now: https://www.redlineautoparts.com/honda-cr-z/ There's always Ebay which is decent for used CR-Z parts depending on what (headlights are always overpriced for example).

Or if you want new (or can't find used) then Genuine OEM Honda Parts and Accessories Online - Honda Parts Now has been good for a bunch of us, here's an east coast alternative: OEM Honda Parts at Majestic Honda | Majestic Honda Automotive Parts, pretty much any of the online OEM Honda parts dealers should beat local dealership parts counter, some by a lot.
 

·
Registered
Joined
·
905 Posts
So there is no way to bench test the fan without the HDS or OBDIIC&C devices you referenced?
You could disassemble the fan and then start visually checking the mosfets and testing them etc
Everything can be tested if you have the skills equipments and time etc.

10A+ 12V Bench Psu.
Decent multimeter.
Oscilloscope maybe.
Pwm source..

If you apply 12V 10A power to the fan and connect the PWM in wire to 12V+ or GND (forgotten which) it should run at full speed IIRC..
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #9 ·
Hi guys,

Just a quick update and a quick verification question - I pulled the fan and tested it like Peter's video that I linked a couple posts up and the fan is indeed pooped. If I put power to it, it sometimes moves a teeny bit but then stops and if I spin the fan it will continue to turn although it clearly doesn't want to so it looks like it has to be replaced.

I checked a bunch of places online (Thank you Koala Yummies), some places are out of stock - but Rock Auto apparently has the fans. In fact, many different fans!

My question - is this the correct part number ?

" 1 J 8 1 6 R M X 0 0 3 " which Rock Auto shows as a VDO / Continental part # of " PM 9503 "

There are other part numbers (such as PM 9504) which look suspicious like my fan and are significantly less expensive.... so would anyone happen to know for sure which part number I need?

Thank you
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #10 ·
I called my local dealer today and he told me the part number was

1 J 8 1 0 R T W 0 0 3

And also said he didn't have the part and wouldn't be able to get one until mid-January. Should I be looking for this RT part # instead of the RM part?
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #11 ·
Now it's looking like I won't be able to get either part for at least 3 weeks.
Can I drive the car without this fan? With the fan unplugged, no fuses blow and the hybrid battery appears to charge. It's near freezing outside and my average trip is less than 20 minutes, maybe 10 - 15 miles.
 

·
Administrator
Joined
·
7,871 Posts
Others have mentioned removing the motor from a Non-CR-Z Honda Hybrid fan and installing it in place of the CR-Z one. Basically move the guts into your existing housing. Anyone have details as to what alternative parts will work?
 

·
Registered
Joined
·
905 Posts
Automotive design Automotive lighting Input device Machine Auto part


You will have to swap over the innards (orange marks) but these should work.

2010 - 2014 Honda Insight Hybrid
2005 - 2007 Honda Accord Hybrid
2006 - 2011 Honda Civic Hybrid

Probably many others as well....

Try it with it unplugged if you want.

But if the MCM tries to command the fan you will get an immediate IMA fault and likely lose the dc-dc charging, so the 12v will die very quickly.
Take a spare fully charged 12v battery, spanners etc.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #16 ·
Good news, Rock Auto came through for me with part # VDO / CONTINENTAL PM9503.

I installed the fan, replaced the fuse and have driven the car a half a dozen times with no issues yet. The fan has turned on a few times and no warning lights yet on the dash - I hope the problem - free running continues🤞.

Thank you all for your help and direction with this issue. Next up, I'd like to look into grid charging like in Peter's videos :


Thanks very much everyone!
 
1 - 19 of 19 Posts
Top