Volvo Engine Service Required Message
This is a message that my Volvo (S80 2004 2.0T) started showing yesterday. The message was accompanied with a yellow/orange warning light, (image on the right) in the car dash.
This freaked me out when it first appeared as I was worried that the car could shutdown anytime while on the move. But apparently the color of the light, yellow, is an indicator that the issue is not major and therefore such a shutdown is not an immediate possibility. On the other hand, if the color of the indicator is red, then it is indeed cause for concern and the best option is to stop the car and seek professional help immediately.
In the past whenever I had issues with my car, my first reaction is to reach out to my mechanic for help. But with the Volvo, what I have learned is that with the amount of electronics and computer control that is embedded into it, it's best to first to research online, narrow down the possible causes to a select few and then approach the mechanic appraising him of your research results. And sometimes you might even be able to fix the issue yourself (like I did with the out of sync door mirror folding issue). Perhaps it's because my mechanic is not very familiar with Volvo that this is necessary. He's more of a VW/Audi guy having worked in their official dealership for many years before venturing out on his own. Unfortunately right now I don't have the time to find a Volvo specialist and this guy's place is close to where I live. More importantly I've found him to be trustworthy.
Anyway with that approach in mind, I started my research yesterday and here are some of my findings. I thought it's best to record them here for my own reference, should this happen again.
Internal Error Codes {#internal-error-codes style="text-align: left;"}
While messages on the console provide a driver friendly generic message, internally the computer associates error codes with each problem and stores it. As many things can go wrong with something like an engine, Volvo displays the generic message 'ENGINE SYSTEM SERVICE REQUIRED' in the messages console, but stores a more discrete error code internally. While the official OBDII reader can obviously read this code, there is an easier way.
According to this post, with the doors closed and engine running, holding down the READ button at the end of the left stalk (used for indicators) along with the trip meter button for 10 seconds should show this code on the messages console, along with a beep.
I searched the web for a list of possible error codes and their description, but unfortunately I have not been able to find one.
Possible Causes for the Message {#possible-causes-for-the-message style="text-align: left;"}
So far my research yielded many threads where others have encountered a similar problem and going through these, I have narrowed down the list of problems to a few:
Cruise Control {#cruise-control style="text-align: left;"}
Somehow the cruise control stops functioning along with this message and I have the same symptom. One owner fixed this by changing the brake diaphragm position sensor and it was fixed.
The post linked above also relates the problem to the cruise control. I remember my car's cruise control stopped working two weeks ago on a trip to Taoyuan. So to be investigated.
Here's another thread that describes this problem and how he fixed it.
And this thread explains how to fix the brake pedal position sensor, without buying a new one.
Random Misfire {#random-misfire style="text-align: left;"}
One owner attributed the problem to this. And I have been experiencing this on and off, but only when I start the car.
This owner pulled all the coils and spark plugs and found two spark plugs were not screwed in tight, which could have meant some compression loss and possibly a random misfire. He cleaned all the plugs and coil connections and also removed all the crumbing plastic sleeve on the wiring to the coils and wrapped all those wires with electrical tape, though he did not see any other damage to the wires, then installed new plastic sleeve. This seems to have fixed the problem as the message did not appear again after resetting it using the same method to reset the service indicator message.