16 replies to this topic

[-JK-]

Hi all,

 

Just thought I'd post something about my experience tonight as I haven't found much on here covering this problem.

 

I had to jump start my car today because (for various reasons) it's been sat at my parent's house for about a month. The battery was completely dead and while the voltage was too low the instruments went crazy with flashing lights, temperature reading 160 etc. but once there was a bit of juice in the battery the car fired up and everything seemed to be working.

 

However, while driving home I noticed the tacho was reading about 1100rpm at idle and the speedo was over-reading by about 10mph across the range. Turns out the instruments had gone out of calibration and the needles were jumping up too much when the ignition is turned on. After some searching around I found this service note from Lotus (  Electrics.pdf   416.11KB   54 downloads), followed the instructions on page 9 and now everything is back to normal 

 

Here's the instructions in case anyone else's speedo/tacho are a bit out:

 

1. Leave driver's door open

2. Hold down trip reset button

3. Turn on ignition

 

The needles will jump down to the bottom and bounce off the stops, release the reset button when this happens. The display will show the version number etc. Now your instruments should be back to factory calibration 

 

Boy am I relieved I didn't permanently damage the cluster! 

Edited by -JK-, 22 February 2015 - 08:48 PM.

[oggster]

good post cheers.

[slindborg]

I'm still bemused as to how having the door open makes any difference, since the wiring diagrams show no link from the door switches to the cluster, or anything that talks to the cluster (since its all discrete io bar the temp signal).

[Claws]

I'm still bemused as to how having the door open makes any difference, since the wiring diagrams show no link from the door switches to the cluster, or anything that talks to the cluster (since its all discrete io bar the temp signal).

It's the through draught, it helps to have the pax window half down and the soft top fitted

[ianrm]

I'm still bemused as to how having the door open makes any difference, since the wiring diagrams show no link from the door switches to the cluster, or anything that talks to the cluster (since its all discrete io bar the temp signal).

 

 

It is so you can make a quick exit if it goes wrong and the cluster explodes.

[-JK-]

I'm still bemused as to how having the door open makes any difference, since the wiring diagrams show no link from the door switches to the cluster, or anything that talks to the cluster (since its all discrete io bar the temp signal).

Doesn't the alarm talk to the cluster to make the red light flash when armed? Don't the door switches talk to the alarm?

[slindborg]

I know on the na, the light for the alarm was in the console behind the gear stick... It could be in the dash on turdos, but you'd need to put the alarm into a mode to relay the door open/closed to the cluster as it would only be a discrete input, there is no fancy pants comms going on to the cluster, no kwp, no Lin, no can, no ethernet I'd like to see why or how the door open does anything, but from the diagrams I can't see it, that's all.

[-JK-]

I know on the na, the light for the alarm was in the console behind the gear stick... It could be in the dash on turdos, but you'd need to put the alarm into a mode to relay the door open/closed to the cluster as it would only be a discrete input, there is no fancy pants comms going on to the cluster, no kwp, no Lin, no can, no ethernet I'd like to see why or how the door open does anything, but from the diagrams I can't see it, that's all.

Dunno, just following the instructions from Lotus (which work). Might not be necessary to leave the door open but I cba to check :-P For reference the shift light (which the NA also doesn't have along with its missing 50bhp) also doubles as the alarm light on the turbo cluster.

Edited by -JK-, 22 February 2015 - 10:42 PM.

[G-Bob]

 

Dunno, just following the instructions from Lotus (which work). Might not be necessary to leave the door open but I cba to check :-P

 

 

did you do it all while hopping on one leg with hankie tied round your neck?

[-JK-]

Alright naysayers, here is a block diagram that clearly shows the driver's door switch is connected to the instrument cluster on the turbo. http://www.speedster...nt (Z20LET).pdf Check out block S38.

Edited by -JK-, 22 February 2015 - 11:21 PM.

[slindborg]

Furry muff, couldn't see it on the actual wiring diagrams from the same place

Edited by slindborg, 23 February 2015 - 09:56 AM.

[Arno]

Lights-on buzzer is inside the dash unit and therefore needs a link to a door switch, usually the driver side.. Pin B11 on the dash AFAIK..

 

Bye, Arno.

[FLD]

I assume this would work with the passenger door?

[jakepeg]

Thanks, Was driving me crazy!

[Mattyboi]

On the N/A are the needles supposed to drop down to the stops when the ignition is turned on?

[Andrew aka Stuwy]

should this not be in the useful topics section?

[anz3001]

Cool, that'll save me the hassle of disconnecting the battery next time I do it.