- Joined
- Dec 5, 2018
- Points
- 70
- Model of Z
- Z4 3.0Si Sport
A word of warning to anyone who’s thinking of fitting a HUD Speedo.
After being very impressed with @T-Tony’s unit I decided to buy one as a lock down present. Identified a suitable unit from the worlds favourite retailer (Amazon).
Fitting it was a piece of cake, plugged into OBD socket, ran the cable and got it positioned to suit. BTW they claim you can use this as in OBD or GPS mode, I could NOT get it to work in GPS mode.
Wind forward several weeks I’d not been using the car as much as normal and during one shopping trip the air bag light came on.
Unplugged the HUD and plugged the scanner in, it did not come on, tried the Carly, it also wouldn’t work, had a minor panic attack and then started to think, checked the fuses, the 5amp (24) fuse had blown, I replaced it and the scanner came to life.
It showed fault 93B2 ACSM: Safety battery terminal.
When I researched this I found it related to a battery terminal that was designed to disconnect the cars electrical system in the event of a crash. Apparently looks like this.
Result !! , however my car doesn’t have one, my battery terminal looks like this
Did some more reading and it seems that SBT doesn’t disconnect all power it just powers down some circuits eg fuel pump etc.
I then had to make a run to the doctors and when I got in the car to leave the surgery it wouldn’t start, cranked ok but wouldn’t fire, on repeated trying the battery ran down after only 2 or 3 attempts and I had to send for the missus, the Merc and & set of jump leads, it started first go on the jump leads and when I got home I put it on charge.
When I tried it again, started no prob, the fault code cleared and has stayed off.
I guess what’s happened is leaving the HUD plugged in was using power, not using the car as much and linked, probably, to the colder weather ran the battery down to the point where the EMS thought the SBT had fired and threw a fault, I guess it was logical, but a bit confusing.
So if you have one of these and you are not using the car as much as normal bear in mind what the consequences could be.
I’m lucky that I have a scanner and could figure this out myself otherwise it would have meant a trip to the garage and even if they were honest and figure this out would probably have cost me a few
After being very impressed with @T-Tony’s unit I decided to buy one as a lock down present. Identified a suitable unit from the worlds favourite retailer (Amazon).
Fitting it was a piece of cake, plugged into OBD socket, ran the cable and got it positioned to suit. BTW they claim you can use this as in OBD or GPS mode, I could NOT get it to work in GPS mode.
Wind forward several weeks I’d not been using the car as much as normal and during one shopping trip the air bag light came on.
Unplugged the HUD and plugged the scanner in, it did not come on, tried the Carly, it also wouldn’t work, had a minor panic attack and then started to think, checked the fuses, the 5amp (24) fuse had blown, I replaced it and the scanner came to life.
It showed fault 93B2 ACSM: Safety battery terminal.
When I researched this I found it related to a battery terminal that was designed to disconnect the cars electrical system in the event of a crash. Apparently looks like this.
Result !! , however my car doesn’t have one, my battery terminal looks like this
Did some more reading and it seems that SBT doesn’t disconnect all power it just powers down some circuits eg fuel pump etc.
I then had to make a run to the doctors and when I got in the car to leave the surgery it wouldn’t start, cranked ok but wouldn’t fire, on repeated trying the battery ran down after only 2 or 3 attempts and I had to send for the missus, the Merc and & set of jump leads, it started first go on the jump leads and when I got home I put it on charge.
When I tried it again, started no prob, the fault code cleared and has stayed off.
I guess what’s happened is leaving the HUD plugged in was using power, not using the car as much and linked, probably, to the colder weather ran the battery down to the point where the EMS thought the SBT had fired and threw a fault, I guess it was logical, but a bit confusing.
So if you have one of these and you are not using the car as much as normal bear in mind what the consequences could be.
I’m lucky that I have a scanner and could figure this out myself otherwise it would have meant a trip to the garage and even if they were honest and figure this out would probably have cost me a few
