C1259 Hybrid Issues on an RX400

[JSeaman]

Hey guys and gals, I am hoping to pick the collective brain about my wife's 2005 RX400. It has been stood for a few weeks and when I drove it today t smelt damp, definite water ingress somewhere, steamy windows etc.

Anyway, about a mile into the journey "Check Hybrid" and "Check VSC" popped up but it was still driving OK. I was only going 2 miles so I parked up and when I returned it wouldn't start due to the "Check Hybrid" warning. I got Techstream on it and had P0AA6 and read about the issue with water getting to the relays under the batteries in the boot. So I whipped the seats out, took off the Battery covers, found a big pile of water and drained it by removing the bung. The relay unit wasn't in bad shape, a tiny bit of green on one of the bus bars but everything else looked good (connectors, pins, relay spades etc). 

I put it back together and P0AA6 has gone but I'm left with a C1259 code for the VSC which I can't clear. I also found my 12V cell down at 10V despite being about 8 weeks old so something is wrong. I am running out of ideas now and was hoping someone could steer me in the right direction. 

[Herbie]

28 minutes ago, JSeaman said:

I put it back together and P0AA6 has gone but I'm left with a C1259 code for the VSC which I can't clear.

If you get the code up again in Techstream you should be able to click on 'List' and it'll give you a subcode that should narrow the cause down.

[JSeaman]

Thank you - will give that a go shortly, going to pop out in 30 mins and recover it on a flatbed, might be able to report back this evening but if not tomorrow

From what I'm reading this might link to the skid control ECU. I have recently change the lower wishbone and did discs and pads, not sure if that can in any way upset anything. Also reading about linear solenoid valve initialisation, not sure if that's worth pursuing yet. I'll get the detailed code and report back either way

[Greisingel]

Welcome to the RX400H wet club  

It may be as simple as POAA6 526 followed by code 612. This will mean water has caused a short in the Battery case. 

You'll probably have water ingress. Plenty on that in various forums. This will mean sealing seams and drying out the car. It’s a pain but fingers crossed not a disaster 

[JSeaman]

Thanks for that, I'll report back soon, still waiting for flatbed

[JSeaman]

OK a little more info, I ran a health check and just had the solar sensors and C1259 under ABS/VSC/TRC

 

Just as I double clicked on this the Battery died:

 

I left it on charge for an hour after getting it trailered back and I had a suite of codes:

I think this is because of the Battery, I managed to get more on the C1259 as follows:

 

Is the Detailed Freeze DTC of 150 the value you were after?

I'm going to leave things on charge over night and then try again in the morning

James

[JSeaman]

OK after a night charging I was greeted with all these codes this morning:

 

I noticed I didn't get the dreaded beep "Check hybrid" but cleared the codes and it fired right up no problem. 

So whatever was wet it wet no longer, I guess I'll just dry everything out as much as I can and put it back together to go leak huntin

[Greisingel]

OK so you don’t have the horrible POAA6 and location short subcodes. You can get READY to start your car. 

Get a new Battery for starters. I had incessant problems with my ageing auxiliary. It simply wouldn’t hold charge. 

I got a 450 CCA Halfords Battery £80. The power isn’t crucial because all It does is power the electronics which instruct the HV Battery to spin the engine. 

Alternatively, order a deep cycle Battery designed for a hybrid (Panasonic) I think. I had to get the cheapest as I’m brassic at the mo and Halfords did the job. Get the one designed for the left engine bay. I got the reverse and grounded live. I was tired and it was dark. 

[JSeaman]

The Battery is about 6-8 weeks old

[Greisingel]

Apols you did originally say. Yes. Parasitic draw of some sort. Or the codes are genuine and mechanicals need attending. I don’t think so

After I cleared my POAA6 I had the VSC and ABS persist. I took it out for a long drive and then tried a DTC clear. That worked, they cleared. I had the solar one for ages and it just disappeared. The tilt should go after a drive and the car resets. 

[Greisingel]

One more thing run max heat blower to the floor. Take it out for an hour or two. The AFS may need a new height adjuster rear driver side. Easy job. £60 replacement part. I think it’s all electrical though. 

[JSeaman]

I think the solar is just because it's cloudy today but I'll take your advice and try a long drive then code read/clear. Hopefully that will get things back on track, appreciate the input 

[Mihanicos]

C1241 refers to Battery voltage too high or too low.

B1421 solar sensor passenger side.  B1424 solar sensor driver side.

B2620 refers to ECU power source malfunction.

B2421 refers to communications interruption.

From the foregoing, you may have a bad 12v Battery. The lowest acceptable value is 11v.  From the techstream display, the 12v Battery voltage had fallen below the minimum threshhold.

Whenever this happens, you get all kinds of non related codes.

The freeze frame should normally give you the sequence of events leading to each code.

Chris.

 

[JSeaman]

Thanks Chris, exactly that - per the first post it was at 10V. I think all were spin offs from that

Just been for a half hour or so at a toasty 27 degree cabin temperature! I also used a hairdryer to get rid of the few damp bits in the rear.

I have put the hybrid Battery covers all back on (I think they used half the world's supply of bolts on that!) and peeled the carpets back a little towards the front seat - sodden! I popped both grommets out and that's draining away now. Next will be front seats out and lots of hairdrying!

Once I've dried out the front I will whip the boot carpet out and check out under there, I think there are probably multiple points of ingress at this stage

[Greisingel]

That’s the way. It is such a shock to see all that soddeness. 

I’m convinced you’ll clear all the codes after use and full dry. 

The tilt should be solved. 

[welland]

What are the solar sensors used for? Where exactly are they located?

[Mihanicos]

The solar sensor for both driver's and passeger's sides is located at the centre of the dashboard very close to the windscreen. You can see it protruting above the dashboard, like a ball about 1.5 cm diameter. It measures the amout of sunlight and the airconditioning output is adjusted accordingly. This feature comes into operation when you select auto function for air conditioning.

Using an incandescent lamp very close to it from outside the windscreen the techstream will show the sensor's output as you vary the distance of the lamp from the sensor. There are tests you can do to determine the fault and repair it.

Chris

[Greisingel]

On 1/30/2021 at 2:51 PM, JSeaman said:

Thanks Chris, exactly that - per the first post it was at 10V. I think all were spin offs from that

Just been for a half hour or so at a toasty 27 degree cabin temperature! I also used a hairdryer to get rid of the few damp bits in the rear.

I have put the hybrid battery covers all back on (I think they used half the world's supply of bolts on that!) and peeled the carpets back a little towards the front seat - sodden! I popped both grommets out and that's draining away now. Next will be front seats out and lots of hairdrying!

Once I've dried out the front I will whip the boot carpet out and check out under there, I think there are probably multiple points of ingress at this stage

How did it all go? Clear all the DTCs? 

Did you clean the rubber Battery drain bungs

[JSeaman]

Hi yes all good thank you for checking - I cleared out about 9 grommets. After a day drying it out it hasn't misbehaved since. I took the boot apart and it was pretty dry there, I think there is a small leak from the rear lights but it is the front that is coming in the most. I took both front seats out and cleaned underneath and but no obvious sign of ingress yet

[Greisingel]

Good to hear. The front footwells could be filling from water ingress via the door cards.

Fully open front doors. Lever window outer rubber seal with plastic spatula and pour water in. Like if it was raining. The water will exit door bottom drain holes as it should. But in some cases the water also leaks in via the base of the card. 

Was it easy to access the rubber drain plugs under the hybrid Battery?  I haven’t gone there yet. I took out some of the floor grommets in the trunk to expose the holes to allow draining. 

[JSeaman]

Thanks, do you mean pour water between the outside of the window and the seal? I'll give that a try and check the door card

 

Yes quite easy to get to the plugs although there must be about 30 10mm nuts/bolts to remove, nothing complicated but just lots of them. If you can take the seats out then you can easily get the drain plugs out, just be careful around the HV stuff!

[JSeaman]

I was intrigued so wedged the door and poured some water in, driver's side (the good side) just came out the drain holes. Passenger side (the one I suspected) came through the door card! I'm not sure quite what the cause is but you're onto something for sure!!

[Greisingel]

Here’s the door test vid. Looks like you’ve spotted the problem. Don’t know what the fix is. probably seal the card base  

Yeah those Battery cover bolts are many. Someone shorted a cell by dropping one in to the matrix. 

[JSeaman]

Found it, the seal behind the door card was not well stuck at the bottom. A new liner and some butyl tape are on order! Thanks for the tip

[Greisingel]

Noted about the seal. I have under carpet wetness on passenger side. I’ll be doing likewise.

I think we have saved ourselves a packet. I wonder sometimes if people have changed their hybrid Battery at great expense when they didn’t need to