1994 850 CEL, Code 112, gas and temp. gauge fault

rebecca8 · Post by **rebecca8** » 16 May 2014, 16:37

Hello,
About 2 weeks ago, I attempted to fix an EGR fault with a new EGR vacuum solenoid. I cleared the code, and the CE stayed off until today. While driving the CEL came on and the car lost power, but kept running. When I started it later today, it was running ok, but I checked the codes, and got a 1-1-2 fault in ECM in port A-2 fuel system. I also got a 1-2-1 for the MAF which I replaced last year with a brand new Bosch. In addition, I noticed the gas and temperature gauge on the dash is not working. I also have a TRACS and ABS light on with the CE. I checked the fuses, but haven't checked any relays yet. Can anyone point me in the right direction? Not sure if it might be related to EGR, although seems like an electrical/computer issue now, maybe due to messed up air/fuel ratio in engine???? The other problems on the dash are throwing me off. Oh, and last week, while I was pulling out of a lot, the car just shut off. It restarted, but I parked it again, and checked spark plugs and some other stuff. It hasn't done the same thing since.

Post by **Ozark Lee** » 16 May 2014, 18:06

Try to clear the codes and see if the 1-1-2 comes back. I have never seen a 1-1-2 since when the ECU craps out completely you can't read any codes from it. One other thing to try is to remove the ECUs and spray the edge connectors with electrical contact cleaner.

The instrument cluster problems may or may not be related. Try reading and then clearing the codes from port A-7. There is a diagnostic mode that you can enter to test the cluster itself but I will need to look up the procedure for you. I'll try to find it this evening and post it back.

...Lee

rebecca8 · Post by **rebecca8** » 16 May 2014, 20:29

Thank you so much. I just re-read the codes b/c someone was talking to me earlier while I was doing it. Sure enough, I only pulled a 1-2-1 on A-2, I wrote it down incorrectly due to the distraction. I believe that's an old code, but I'll be checking anyway. I also took a closer look at my blower motor through the glove box. I had been having some trouble with the connection. I disconnected the power from the motor, and did not see anything unusual in the wire harness connector. Then I pulled off this other black piece that connects directly into the blower motor. The metal contacts are VERY dirty. Do you think a bad connection at the blower motor could cause a loss of power due to some weird incomplete flow of electricity, and now illuminate the other lights mentioned? I wish the wiring diagrams were still on this site.

Post by **Ozark Lee** » 17 May 2014, 09:28

The blower motor contacts tend to get hot and discolored through normal use. Clean the connector up the best you can and soldier on with that one. There are two other contacts inside the blower motor housing that also overheat and cause problems.

Given all of the symptoms, and their somewhat random nature, I think you may actually have a problem with the electrical portion of the ignition switch. That too is a high failure rate item and the ABS/TRACS lights coming on at times is a tell.

Check the connector on the MAF for any signs of corrosion. Volvo has a service bulletin out that actually calls for using a ty wrap to secure the MAF connector.

I also found the instrument cluster test mode. It is DTC-3. With the flywire in port A-7 press the button three times. The cluster should respond by going to mid scale on all gauges except the temp gauge which should go to the bottom of the red. It should also click off .5 miles on the odometer. If the cluster passes the internal test but still doesn't read correctly then you will need to track down the wiring problem but the connectors on the cluster are a good place to start.

The simplified schematics are in the factory service manual but you can get the detailed schematics here:

http://www.volvowiringdiagrams.com/

...Lee

rebecca8 · Post by **rebecca8** » 19 May 2014, 18:05

Thank you. I checked the MAF, it looked ok. I replaced the air filter, although it didn't look too bad.The CE light hasn't come back on. Considering that the MAF is less than 2 years old, I'm wondering if anything else could trip that 1-2-1 code. I cleaned the connection for the blower motor, and "adjusted it." Works good now. I will try the instrument cluster test mode, haven't done that yet, to see what was going on with the other dash lights. Thanks for the diagram link. Awhile back, I spent hours looking at those on this site trying to fix another issue. Greatly appreciated.