P0113 (intake Air Temperature High Voltage) - Fixed!

[stickman007]

Hi guys,My engine light just started to turn on last night after a wash, and I just want to throw it out to the community to see if anybody has experience this before...Recently I've done the following mods...don't think that they're related, but just in case:EGR emulator (been running fine without issues for 3 months)Evilution ESP on/off using the dash dimmer switchThe code cannot be deleted when the engine is on, but can be erased when the engine is not running, and ignition is on. I can delete the code, turn the engine on...and the light will stay off. The next time I start the car, it'll be back. Unfortunately I do not have a reader that can show me the actual temperature reading right now.Going outside now to check wiring harness now...hope to hear from you guys.Izzy

Edited July 15, 2012 by stickman007

[stickman007]

Fixed! Turns out that my white wire going to the IAT sensor was broken off complete at the connector. All I had to do was gut the connector and resolder the wire on to the female pin and reassemble the connector and voila!Anybody else found it really hard to find electrical connector pins?? I ran around town looking for a match and nobody carries them! When I did my ESP mod...I had to order the iso pins from UK...and they sell in packs of 30, now I have 29 extra since I only needed one! Izzy

[3UP]

I had the same code today the yellow wire corroded off the IAT , I disassembled the connector and soldered a new wire , heat shrunk and sealed it all back up . This site is so easy just type my code in the search and somebody already tells you the problem and the fix . Thanks guys.

Edited January 29, 2014 by 3UP

[Francesco]

Threadsurrection time!

Has anybody had very erratic IAT readings alongside the P0113 code? Whether coincidental to my ungluing Velcro problem with my ScanGauge or not, after I clear the code I drive with IAT as one of my XGauges and the indication rotates between 29°C, 70°C, 152°C and -39°C. Has anybody else seen this? I thought a faulty wire would just show -39° but I honestly don't know how long this has been going on, as I never use the IAT gauge. Could this be affecting fuel economy as well as power? Both have gone down in recent months.

[MikeT]

I would say yes, those are some oddball readings!!

[Francesco]

I'll have a crawl underneath this morning to check the wires, and likely fashion a new Red Green scoop as well.

[David_18]

I had this code last winter and temp show - 39. Both wire were rusty and were eventually cut.

Where i saw that, i through that was the cause of my cold hard starting, but no change at the end..

Edited August 4, 2015 by David_18

[Alex]

A bad or loose connection will absolutely show an erratically changing temperature. No connection the computer will know and show a code (if programmed to do so), but a bad one does give wildly erratic readings.

[dmoonen]

It sill screws up starting conditions on most engines and how the engine runs, on my tdi had to change mine last week eventually it was causing a delay in starting. I ran into it it on three of my smarts, broken wiring for the most part and a pooched sensor on the Brabus due to me accidentally crushing it.

[Francesco]

And as expected... White wire cut almost all the way through, flush with the connector, and it broke off completely when I jiggled the connector free of the sensor. Rather than futzing with the connector and hoping to find a suitable pin in my junk drawers, I called West Island MB and Pierre in Parts found a matching connector from an M271 available in Toronto. $18 or so for the plug and pins, saving me quite a bit of hassle. I'll get it back in on Thursday and see if my FE goes up and the top end feels a bit breezier...

[tolsen]

A repair kit is available from Smart. Just a plug with short cable. Part number Q0004633V008000000

The plug fits all temperature sensors on a Smart 450.

[Francesco]

I'll wait to see if the plug I'm getting is correct before enquiring with that number; every online seller of that part wants 30€+ excluding shipping!

TK, do you believe the erratic readings could affect fuel mapping significantly?

[tolsen]

I doubt that it will affect engine performance much but pretty sure open circuit will make intercooler fan run continuously.

[tolsen]

They cost about £22 here.

http://www.smart-stuff.co.uk/wiring-repair-sets-429-c.asp

[Francesco]

Open circuit (0V) gives a -39°C reading, so the fan does not come on.

[tolsen]

My fan runs all the time when I unplug iat sensor.

[Francesco]

As (unfortunately) expected, the connector proposed had the locating tabs in the wrong place. I gave Pierre the number TK offered above and sure enough the dealership had one in stock. RRP? $55 plus tax. With my CsQ discount I paid $47 plus tax. Jeedoof.

[tolsen]

Bloody expensive if you ask me. We need to treat those connectors as if they were gold. Remember, each Smart 450 has three of them.

[Francesco]

Yes, I just cleaned the OAT connector yesterday, and the water temperature connector in late winter when I replaced the thermostat. Even at £22 it is way overpriced, considering I got a bag of 20 full AMP male and female connectors with pins, grommets and seals for $15.

[MikeT]

22 quid these days is about $47 anyway.

[Francesco]

Yep.

[Francesco]

Data points: normal commute, half suburban traffic, half highway, ambient air temperature 25°C. Both IAT and WT started at ambient and climbed progressively, fan off. Before hitting the highway, IAT climbed to 61° when the fan came on and then it dropped to 44° and settled there. As I accelerated to 120 km/h, IAT once again climbed to 59° then dropped and settled at 45° with the fan going once again. Water climbed to its normal peak of 95° -- seemingly the new thermostat's full opening temperature -- and settled to 89° for the remainder of the ride. Exiting the highway with reduced load, the fan turned off at 43° and the temperature quickly dropped into the low 30s as I cruised the rest of the way to work with no traffic and normal street speeds from 40-65 km/h. The oil-jug scoop works well.

[tolsen]

Sounds like all is back to normal. Interesting to learn you have a similar scoop to mine.

Clips at side made from stainless steel sheet metal.

My latest improvement is replacing the plastic rivet seen on the left with a stainless steel M5 mm hex bolt and penny washer. Drilled out hole in transmission for plastic rivet and fitted a stainless steel M5 rivnut. Now less chance of the scoop dropping off. i might post some photos of this mod at a later date.

[Francesco]

I've managed to lose one of the two steel clips as the last time the scoop was shorn it broke above the clip point on the inboard side. I've temporarily secured that side with a zip-tie but looks like I'll be sourcing another new scoop and fabbing new clips. I forget, are the two clips identical? I think I'll also try to come up with some kind of "disposable" lower edge in place of the flap that seems to rip apart the entire scoop.

[tolsen]

The two clip at side are identical. I strongly recommend you replace the plastic rivet with a proper M5 bolt and penny washer. That is an easy fix but will require lowering of transmission to get sufficient access for drilling out hole and fitting rivnut. Aluminium rivnuts won't last long, must be stainless steel.