P0031, P0051, P0057 and P0102 codes on 2008 RX400h

[ColinBarber]

1 hour ago, Clive-D said:

True - they are next to each other in Guildford! Is it safe to drive or shall I get it trailered in?

 

Toyota Guildford won't touch it, the Lexus dealership is owned by the same franchise and so they will only let the right hand side building work on it.

[m4rkw]

http://www.toyotec.co.uk/services.html

These guys did my gearbox fluid change when I first got my car, they seemed to know what they were doing. I think there are a few toyota specialists in surrey.

[BachelorDays]

52 minutes ago, ColinBarber said:

No, that is normally an electrical issue unless there is a problem with the inverter. I'd try another 12v battery first if you can.

That would also explain why you noticed the engine coming on more.  The problem is no one seems to relate this issue with a known/ experienced problem.

If its a wire or connection going bad over time and eventually giving way then Lexus or a Toyota Independent will fix it without too much effort - and probably not be too different on cost.  I would put the malfunction closer to the Inverter end than the 12v Battery end.

The electrical buzzing & electrical burning smell would all be consistent except that you had that wash (jets and all).  Remove the Battery and have a good look around.  You might find an obvious loose/ burnt connection.

[m4rkw]

Halfords will test the Battery for free.

[Delphius1]

Hybrid errors can be generated by voltage issues on the 12v system instigated by invertor errors. The invertor is used to downconvert from the high hybrid Battery voltage go the low 12v system voltage.

Multiple errors seems to suggest a voltage error but with a cause affecting multiple systems. 

 

I'd suspect an earth fault. The fizzing noise could be arcing across a poor earth for instance. Poor earths are good at causing multiple issues.

[Clive-D]

Hi all, thanks for all the help and suggestions - I have positive news!

Something in me wasn't buying the earthing issue - all I checked on the multimeter was 100% good, and the aux battery checked out ok. Main issues that pointed to the Mass Air Flow sensor were lumpy tickover, dramatically increased fuel consumption, and (no idea about this but found it twice on YouTube) unplugging the connection to the MAF sensor when the engine is running doesn't cut the engine. So I thought I'd bite the bullet and replace it before I get Lexus involved.

Bought a Denso one (same as the one fitted) online from Euro Car Parts for £153.99 - stayed away from the £30 eBay ones!!

Arrived today. Before I fitted it, I tried switching on with nothing on (climate, radio, lights) to see if warnings were still there - had a thought the car washing guys may have got water in somewhere which mat have dried out... got the previous warning Check Hybrid System but a nasty new one Check four-wheel drive system.

Changed the sensor, 2 minute job, switched on and bingo, all nasty warnings gone. Engine started and still ticked over rough so I took the car for a gentle run. Ran as sweet as you like, but the engine light still on. When warm I parked up twice and switched off, but it was still on when back home, HOWEVER I can't tell when the engine is running or not now. It cuts out as soon as I stop and there is no smell, or nasty electrical fizzing.

Guys, all I have talked about would appear to related to the MAF sensor which I've read will go at around 120k if it is going to. My car is 125k. Such an easy fix if this is it (fingers crossed). I hope the engine light will correct itself and with it the only error code P0102, Mass air flow volume low. Is it possible a non Toyota MAF sensor will need resetting with better equipment than I have? I'll do some more miles and see - fuel consumption back to normal too as far as I can tell after a few miles.

[Clive-D]

On 9/15/2018 at 8:23 PM, m4rkw said:

http://www.toyotec.co.uk/services.html

These guys did my gearbox fluid change when I first got my car, they seemed to know what they were doing. I think there are a few toyota specialists in surrey.

Thanks for this M4rkw - I've bookmarked it

[m4rkw]

@Clive-D sounds like good news. Lets hope that the MAF failing was the only problem and that it wasn't something else, like say a bad earth, that caused the MAF to burn out and die.

Regarding the light, you may be able to clear the error with techstream if you have it, or it may be that the computer runs a specific test only under certain conditions. For example the test that relates to the EVAP emissions system will only run when the fuel tank is above 1/4 and below 3/4 of fuel, and possibly also only when the engine is run up to temperature for enough time. I've no idea if there are similar tests for MAF-related issues, most likely it's just a persistent error code that needs to be reset manually with a scan tool like techstream.

[BachelorDays]

At least its driving again!  I have some odd stories about MAFs - but first, are you saying that the codes come back after you've cleared them with your OBD scanner?  If so, are the codes the same?

[welland]

On 9/14/2018 at 7:57 PM, ColinBarber said:

Engine check light normally goes out after 3 engine start/run cycles with no fault detected, doesn't really matter how many miles each trip is as long as it gets up to a reasonable operating temperature each time.

You can disconnect the battery for 30 seconds however you will need to re-initialise the sunroof/windows/power hatch. You won't lose radio or sat nav presets though. Whatever app you used to read the codes appears to have a clear codes option at the bottom, that will clear the warning light and easier than disconnecting the battery.

It could of been a temporary glitch but if the warning lights don't go out, or you get the errors again then definitely check the battery -ve connection, and earth straps going to the engine as it really seemed like an electrical issue.

I doubt cleaning the sensor would stop those faults occurring, and the heater errors are essentially unrelated, but it will likely restore some smoother running and better economy if it was very dirty.

 

On 9/15/2018 at 5:10 PM, Clive-D said:

Hi Colin

Drove the car today and had it washed at Tesco 🙂 so it's had more than three starts. Warning light still on. Cleared the codes and engine light came immediately back on and I got the same error codes.

 

On 9/14/2018 at 7:57 PM, ColinBarber said:

Engine check light normally goes out after 3 engine start/run cycles with no fault detected, doesn't really matter how many miles each trip is as long as it gets up to a reasonable operating temperature each time.

Sorry everyone, I have the two quotes in the wrong chronological order......

Anyway, I had a fault reported with my MGR about 6 months ago.  When I reset the fault, it came back sometimes in 5 minutes, or sometimes longer, maybe half an hour later, or maybe the next day.  ANyway, after 2 or 3 weeks, the fault stopped being reported, and it has not been reported since.  

A vouple of months ago, I did plug in my OBD2 tester and discovered that the fault is still stored as an old fault, but I did not clear that fault message.  

Question is this:  Is the recorded historic fault anything to do with the fact that the fault is no longer being shown on the dash?  Or, can I assume that the fault has not recurred since the dashboard warnings stopped being reported?  Putting this another way, if I clear the stored fault, will it cause the fault to come back on the dashboard again?  

[m4rkw]

Just now, welland said:

Question is this:  Is the recorded historic fault anything to do with the fact that the fault is no longer being shown on the dash?  Or, can I assume that the fault has not recurred since the dashboard warnings stopped being reported?  Putting this another way, if I clear the stored fault, will it cause the fault to come back on the dashboard again?  

The fault indicated on the dash is a *current* error condition. The codes stored in the computer's history are historic error conditions. If the light is out it means the error condition is not currently present, you can safely delete the history without causing any lights to appear. Of course if the fault is still present but very intermittent there is a chance it may come back at some point anyway.

[Clive-D]

On 9/18/2018 at 10:19 PM, BachelorDays said:

At least its driving again!  I have some odd stories about MAFs - but first, are you saying that the codes come back after you've cleared them with your OBD scanner?  If so, are the codes the same?

Only the P0102, all the others have cleared, along with red triangle warning for the hybrid system. 

Will be doing three 10-15 mile journeys tomorrow so we will see!

[m4rkw]

2 minutes ago, Clive-D said:

Only the P0102, all the others have cleared, along with red triangle warning for the hybrid system. 

Will be doing three 10-15 mile journeys tomorrow so we will see!

https://www.obd-codes.com/p0102   seems like something related to the MAF is still not quite right. 

[Clive-D]

Last Wednesday I drove 12 miles no problem. Went to leave 4 hrs later and all the warnings were back plus a high whistle alert sound. Switched on and off and eventually got rid of the alerts except the engine light. Called my breakdown cover people and they sent out a guy who cleared the codes using his Bosch gear. Drove home no problem. Next day same thing but cleared ok. Coming home was slow to get codes cleared.  Advised the sensor may need programming in. No point going to Lexus as they’ll blame the OEM part. 

So I’ve left a message with an auto-electrics specialist to see if he can sort it. Will give an update when I can. 

[BachelorDays]

On 9/23/2018 at 7:10 PM, Clive-D said:

Last Wednesday I drove 12 miles no problem. Went to leave 4 hrs later and all the warnings were back plus a high whistle alert sound. Switched on and off and eventually got rid of the alerts except the engine light. Called my breakdown cover people and they sent out a guy who cleared the codes using his Bosch gear. Drove home no problem. Next day same thing but cleared ok. Coming home was slow to get codes cleared.  Advised the sensor may need programming in. No point going to Lexus as they’ll blame the OEM part. 

So I’ve left a message with an auto-electrics specialist to see if he can sort it. Will give an update when I can. 

There's no programming in with the MAF usually.  If the code comes back it's because the fault is still being triggered.

OEM part for MAF..  not a Chinese 'original'?

Elecs specialist likely best bet.  Dodgy fuse (in the main fuse compartment in engine bay**), earth points, maybe even a loose MAF connector. 

**Never play with the fuses with the key anywhere near the ignition.

Best of luck!

[Clive-D]

12 minutes ago, BachelorDays said:

There's no programming in with the MAF usually.  If the code comes back it's because the fault is still being triggered.

OEM part for MAF..  not a Chinese 'original'?

Elecs specialist likely best bet.  Dodgy fuse (in the main fuse compartment in engine bay**), earth points, maybe even a loose MAF connector. 

**Never play with the fuses with the key anywhere near the ignition.

Best of luck!

I think you are right - car going in on Wednesday so we will see. I've attached the Euro Car Parts item - it's Denso, made in Vietnam - just off China 😉 the same in all bar the Toyota name.

[Rutlandlex]

Hope you get a conclusive diagnosis tomorrow Clive.  I have noticed that mine lately doesn't shut off the engine at times when I would expect it to but my Battery is 3 years old now so I suspect that it isn't charging up enough.  I wouldn't rule out the Battery on yours despite its age as the quality of the current might not be good when power is being drawn from it.  Modern cars can appear to have a totally healthy Battery but exhibit weird symptoms only for all of those problems to disappear with a simple change of Battery.

Please let us know the outcome.

[Clive-D]

6 hours ago, Rutlandlex said:

Hope you get a conclusive diagnosis tomorrow Clive.  I have noticed that mine lately doesn't shut off the engine at times when I would expect it to but my battery is 3 years old now so I suspect that it isn't charging up enough.  I wouldn't rule out the battery on yours despite its age as the quality of the current might not be good when power is being drawn from it.  Modern cars can appear to have a totally healthy battery but exhibit weird symptoms only for all of those problems to disappear with a simple change of battery.

Please let us know the outcome.

I'll keep you posted - what's your mileage? Not wishing to pre-empt anything, my problems started with the engine not cutting out, also ticking over a bit rough. It's an interesting one...

[Rutlandlex]

Mine's just coming up to 123k hence why I'm following this thread with interest 😬

[Clive-D]

David Hammond of Hammond Auto Electrics in Guildford is the guy looking at it. Drove over with just the engine light on. He's had a look and found a fuse gone that (I think) is on the circuit that sends data from the MAF sensor. One of the four O2 sensors is faulty, plus some other bits I can't remember what he said! Not tragic and likely the old sensor was ok. So pleased this isn't being looked at by Lexus, they'd be fitting all sorts I expect!

He's keeping the car in overnight as he needs it cold to check the rest. He also told me the AFS sensor warning light, which was on when I bought the car, is the front one not the rear, so he's done me a favour there, I was about to remove the rear one and try to fix it. He will check when it's on the ramp as it might just be a corroded wire. Good man, recommend him.

Hopeful that I'll have a better car soon.

[Clive-D]

Got the car back today. 3 hours labour, no parts required. 

He found error codes relating to the MAF sensor and all 02 sensors (same as me). He found a blown fuse and replaced it, cleared the codes and test drove. Fault returned but fuse not blown. Scan found fault on 02 sensor 2, band 1. On the ramp he found damage to the wiring loom - he reckoned due to the car grounding or such like. He cut out the bad section and repaired it. Cleared the codes, test drive again and all ok.

I doubt I would have ever found that! But as someone said, get it checked before you start replacing parts.

On the short drive back, the hybrid Battery went from very run down to very well charged - green, one bar from the top. A bit early to say, but it felt like the hybrid system was charging more than needed and the consumption was lower than I'd expect in town driving. That said, it drove down our road on Battery so maybe it's settling in.

On 9/26/2018 at 1:15 PM, Rutlandlex said:

Mine's just coming up to 123k hence why I'm following this thread with interest 😬

I wouldn't worry! This was and interesting mix of one of those things rather than a mileage related incident. If your car has good history it should be fine. 

What was good to hear was David said he doesn't do much work on these, which implies they don't have many issues. Happy to have the car back, driving beautifully as usual.

[m4rkw]

Glad you got it fixed :)  Have you tried plugging your old maf back in to see if it was really faulty?

[Clive-D]

1 minute ago, m4rkw said:

Glad you got it fixed 🙂  Have you tried plugging your old maf back in to see if it was really faulty?

Thought about it - if the car's going fine why tempt fate! If the consumption stays down I'll try. The guy reckons the old sensor was probably ok. I'll put it in the spares dept 😉

 

[m4rkw]

50 minutes ago, Clive-D said:

Thought about it - if the car's going fine why tempt fate! If the consumption stays down I'll try. The guy reckons the old sensor was probably ok. I'll put it in the spares dept 😉

 

Lesson learned, never buy parts without a diagnosis :)

[BachelorDays]

Great news on the car!  I'm sure the hybrid system is settling in after all these electrical blips.

Do be mindful of a couple of potential loose ends. 

1.  Which fuse and why it blew?  If it was the broken wiring of the sensor (and this isn't very unusual given its unprotected and underneath the car) then that's fine but you need to know.

2.  The undercarriage needs a good examination to see if there's anything else that needs attention before it causes a scare.