2001 V70: ECM-902B throttle unit communication; signal too low

[daniellegend]

Hi all!

I have a question regarding our 2001 V70.
Last week, the V70 started having issues. I know nothing about cars, but my boyfriend, who does have a little bit of car-knowledge, eventually figured that the throttle body was malfunctioning since he took a look at the inside, and nothing was happening once I'd press the gas pedal. No movement at all.

We got it towed to a car garage any my boyfriend shared his assumptions, but was very quickly shut down because he isn't a mechanic. The mechanic said that it was something with the air mass meter (?) and a good €260,- and 3 days later, we were able to pick the V70 back up.

Everything seemed fine and we were happy that we could go out as a family again (we have a 7 month old son!).

A good 28ish hours after we got the V70 back, we were on our way to pick some friends up at the train station. Didn't feel or see anything out of the ordinary, until we pulled into a parking spot. The second we were standing still, the engine shut off on its own. We let the car cool down for a few minutes, and then, when we started it, we were met with the exact same problem as before.

We called roadside assistance and they eventually came to see what was up. And just like my boyfriend had said to the mechanic a few days prior, we got: "ECM-902B throttle unit communication; signal too low". So the throttle body.

This happened last friday. We got the car towed back to the garage but I feel like they're either going to mess up again (we've been there before for my bf's VW Caddy and still have to go back to get some stuff fixed) or set a very high price for the repair.

Could anyone explain to me what exactly could be wrong? And how we were able to drive over 100km (111 to be exact, thanks Life360) over the span of +/- 28 hours with no issues, only for it to randomly come back the second we park the car?

What could possible fixes be? And would I, with the help of my boyfriend and perhaps some YouTube videos or such, be able to fix this myself? Or would I need an actual mechanic to do this? Since I've read before that it'd need to be calibrated or something along those lines.

Thanks in advance for the replies. I truly appreciate it!

Regards,

Daniëlle

[abscate]

The throttle bodies can go sporadically. Working sometimes, then faulting. It’s very possible it started working again , now has quit again.

You can get a used contactless one for about $150

[jonesg]

you need to find a volvo specialist to look at it, volvo systems are inter-related.
It could be one of many things, and throwing parts at it is very expensive with no assurance you fix anything.
As the throttle does not respond is not a diagnosis of throttle body problems, a bad brake controller can inhibit throttle and cruise control.

[volvolugnut]

Working then not working problems can be caused by bad electrical connections. Age, corrosion and loose fits at the connection can be a cause of bad connections.
If you open the hood and have someone listen while the key is turned to position 2, but not start to crank engine, you should hear a low buzz for a few seconds. This is the ETM initial startup. If you get no buzz, the ETM has no power or is not functional.

You could try wiggling the connector to the Electronic Throttle Module (ETM) under the intake manifold or try connecting and disconnecting the electrical connector to the ETM.
If this still V70 has the original throttle ETM, it may have the typical failure with age. See this massive thread
viewtopic.php?t=17252
volvolugnut

[ZackGlynn]

Working then not working problems can be caused by bad electrical connections. Age, corrosion and loose fits at the connection can be a cause of bad connections.
If you open the hood and have someone listen while the key is turned to position 2, but not start to crank engine, you should hear a low buzz for a few seconds. This is the ETM initial startup. If you get no buzz, the ETM has no power or is not functional.

You could try wiggling the connector to the Electronic Throttle Module (ETM) under the intake manifold or try connecting and disconnecting the electrical connector to the ETM.
If this still V70 has the original throttle ETM, it may have the typical failure with age. See this massive thread
viewtopic.php?t=17252getting over it
volvolugnut

Thanks, I will try your way.

[Kolostealthtt]

New xemodex etm installed car ran great for 24hrs, then 2 tps potentiometer codes for tps 1 and 2. Limp mode. Checked etm ground harness good. Did I get a bad etm?