Hey guys,
I've had issues starting my car when it's hot and an electronically competent friend asked me to find out if my car has a body control unit and if so, where is it located?
He thinks it's probably a broken solder seeing it starts fine when it cools down.
Any advice appreciated :)
Ok thanks. Can they be taken apart and repaired or would i need a new unit?
I had a problem with a similarly aged yet different vehicle. Would not start when hot. Sometimes would loose power randomly too. The problem was the air mass flow meter. I was able to take it to a competent mechanic when it was faulty. If the car has ODB you may see other info.
other things to check are ignition coils, crankshaft sensor. Each coil can be removed, then checked with a screwdriver after it has died, to look for spark. slight chance of being slightly zapped, so avoid if you have a heart condition or pacemaker. If you have spark, then it is your coils. more ideas: https://forums.whirlpool.net.au/archive/2667692 I'd also look into cleaning the alternator brushes or replacing it.
the 1.6 has only 2 coils and works on a lost spark system. The coil sits on 1 spark plug and there is a HT lead going to the adjacent sparkler
No.
Does it crank and not start, or not crank?
CAS?
Hey guys
Yeah the battery tested fine. The car let me down today when I tried a restart after an hour drive into town…. After about 30 attempts I jagged a crook sounding start and it ran fine all the way home.
Wouldn't start back at home though when it was hot. Let it cool down and it's started fine since.
My mate reckons he had an issue in his falcon the same and it was a broken solder on one of the modules that the heat exacerbated. May have been in the body control unit on his.
Did your mate fix his or did he perfect the ford punch?
You still haven't answered my simple question. Does it crank and not start, or not crank at all?
Yep, cranks but not starts when the engines really hot.
Quite possibly something as simple as a crank sensor. Does the tacho move when it's cranking?
@brendanm: I don't think it does. Initially we thought it was an issue with the ignition not recognising the key but it cranking when cold ruled that out
@Shane34: Next time it does it, use a bit of water or an aerosol spray to cool down the crank sensor, then try to start it again.
It's most likely going to be a component under the bonnet rather than a computer. Check the error codes on ECU for clues.
We have a 2000 Mazda 323 (same car as your laser). There's no BCM AFAIK.
We were having issues last year where when the engine was at NOT after 30+ mins driving on a hot day, it would stop and then we had to wait 10mins for a restart.
After advice on this forum I changed the cam position sensor. It's been fine ever since.
It was ~$80 at Repco and 10 minutes easy work with a 10mm spanner to change
Could anyone tell me where the immobilizer module is located? Seems to be a possibility too..
One suggestion would be to look into the parts that make the car go (eg cam sensors etc..), rather than the ones that make it stop. Items that make the car go are more likely to make it stop. I agree that they may not be the issue. However, they are the items that would reasonably be expected to fail. Further, as has been suggested, it should possible to ask the car how it feels when it is sick (error codes). That is the best path to take. If one can be sourced, keep a diagnostic device with you. Good luck with your mission.
The immobiliser is in the ecu. It's not going to be affected by heat as a general rule.
What do they do for ecu faults? Probably need to replace ecu, ignition and keys? We're fairly sure it's immobilizer related as immobilizer key symbol wouldn't come on when it was cranking and not starting.
I may actually be wrong about immobiliser being in ecu, depending on what model you actually have, and what engine.
Does the immobiliser light come on normally when trying to start?
Hey guys,
My car model does not support onboard diagnostics.
How will I find the manual error codes for a 2000 bj mazda/ford laser?
Cheers
Thanks mate. We've got the diagnostic process sorted. Just gotta wait till it plays up again as we unhooked the battery testing stuff and lost the error code. Dodgy backyard mechanics lol
ECM only I'm guessing