96 850 GLT Odometer , dumb question

[joe_pinehill]

I was thinking about ordering the gears to repair the odometer. then thought, why bother? I don't plan on selling the car. The speedo works, the fuel gauge works. So I'm thinking why bother? Other than being annoying, what am I missing?

I hate to dig into the dash, and end bending a connector pin or cracking something.

[erikv11]

There are a few minor implications but I think the main disadvantage to a broken odometer is you can't track the miles that accumulate to signal routine maintenance like rotating the tires and changing the oil. If you just always do those things by the calendar or some other method (e.g. when the tires start to show uneven wear), then you could certainly get by without it.

[ehazel88]

Also in some states, they will catch on with your stickers. I write stickers and unfortunately you have to fail a car for something that stupid. erikv11 is explaining why as well, as why it would fail

[rspi]

If your car has the trip computer built in, you can reset it and check the trip mileage on it weekly. Not sure if it goes beyond 10,000 miles, which will make it hard to track timing belt change schedule.

I guess I'd fix it. Pull the dash pad and the cluster comes out in seconds.

[esl_97_850_T5]

joe_pinehill,

1. Like you, I didn't want to remove the dash unless forced to. I've decided to delay indefinitely the odometer fix. But in my case, I decided to figure out how to read the vehicle mileage from the Instrument Cluster, then publish it, so everyone in the '96-'97 850 community can read their mileage the 1st time for a low cost, and read it afterwards repeatedly for free.

See the How to read 1996-1997 Volvo 850 mileage with an ELM327 thread to get you started.

In the 1st post, the one dated 2013-05-25, read from the beginning down thru: It will attempt to interpret the communication and display (what is thought to be) the "Vehicle Mileage" and the "Mileage at Service Light Reset. Those instructions are for if you want to issue the commands interactively.

2. For a quicker (after the initial setup), more automated approach, if you use Microsoft Windows as your operating system, I'd suggest:

- Download and install the free Realterm terminal emulator.
- Download and extract the latest, free volvo850diag.zip distribution.
- With Internet Explorer, display the "local" version of volvo850diag.html (extracted from volvo850diag.zip v0.5 or higher).
- Follow the instructions in the "Requirements" and "Installation and Setup of volvo850diag" sections of volvo850diag.htm. It is important that you either define the RT_ELM327_LOGS_DIR environment variable or else be content with using a temporary directory for the automatically generated log files.
- Exit volvo850diag.

You should only have to do the above steps the very first time.

The following is what you would do in the future when you wanted to read your mileage:

- Plug in ELM327 to Volvo's OBDII port then your computer USB (or serial) port.
- Turn ignition to pos II.
- Display the "local" version of volvo850diag.html.
- Click the bar at the top, click Allow ActiveX, and answer Yes to a couple more questions relating to ActiveX.
- Press the Enter key or click Start Realterm.
- Move the Realterm and volvo850diag windows so you can see them simultaneously.
- Move the Realterm Terminal pane vertical scroll bar to the bottom (so you see the latest communication exchange).
- Press the Enter key or click volvo850diag's My Extra Scans button (since it has an imbedded Minimal Scan which reads the vehicle mileage as well as the DTCs for emissions diagnostics, COMBI, SRS, ABS, and AW 50-42).
- Click Cleanup.
- Click Close Realterm.
- Submit the contents of the Realterm log to the Volvo 850 keyword D3 B0 protocol interpreter by pasting into the box at the bottom of the page, then pressing Interpret.
- Read the Gleanings at the bottom of the Results page that appears in ~10 seconds.

There are other ways to read the vehicle mileage. This is the probably the quickest one, if you want to avoid typing any of the commands and if you want to avoid manual performing the mileage calculation yourself (as explained in B90300).

Summary: get hooked up, display "local" volvo850diag, Start Realterm, My Extra Scans, Cleanup, Close Realterm, paste into kwpd3b0_interpreter.

Alternative #1: Same as Summary, except replace My Extra Scans with either Quick Scan All ECUs or Full Scan All ECUs. They take longer to run.

Alternative #2: Same as Summary, except replace My Extra Scans with ATZ Setup for ECUs 51/58/01/6E/2E/2F, ECU 51 Setup, ECU 51 Read DTCs, ECU 51 Quick Scan (or ECU 51 Full Scan). The time for this alternative is midway between Summary and Alternative #1.

3. If those two approaches of reading the total mileage are too complicated for you, then I'd suggest to use rspi's simple approach of using the trip computer. I usually let my trip computer's 10000 mile odometer [up to 9999 miles] run until it rolls over. The only time I reset it is:

a) when needing to make mileage measurements down to 0.1 -- that resolution can only be done between 0.0 and 999.9, or
b) when accidentily draining or purposefully disconnecting the battery.

The occasional reading of the vehicle mileage via ECU 51's B90300 (or A50701 or A50901) every few weeks or months in conjunction with using the Trip Computer's odometer is a workable alternative to getting the mechanical odometer fixed.

esl_97_850_T5

[erikv11]

I thought the trip computer only goes to 999 miles??

[esl_97_850_T5]

My 1997 Volvo 850 T5 trip computer goes to 9999. It first displays as 0.0 to 999.9, then transitions into 1000 to 9999, then repeats, beginning again at 0.0. I've witnessed two of the 999.9 to 1000 transitions and one of the 9999 to 0.0 transitions.

I'll edit the earlier post from "10000 mile odometer " to "10000 mile odometer (up to 9999 miles)" and "0-999.9" to "0.0-999.9".

[erikv11]

I've never run it that far. Great info, thanks for posting.