Jetronic: Difference between revisions

Digital fuel injection, introduced for California bound 1982 [[Volvo 240]] models. The 'LH' stands for {{lang-de|"Luftmasse-Hitzdraht"}} - the [[anemometer#Hot-wire anemometers|hotwire anemometer]] technology used to determine the [[mass]] of air into the engine. This [[mass flow sensor|air mass meter]] is called HLM2 (''Hitzdraht-LuftMassenmesserHitzdrahtluftmassenmesser'' 2) by Bosch. The LH-Jetronic was mostly used by [[Scandinavia]]n car manufacturers, and by sports and luxury cars produced in small quantities, such as [[Porsche 928]]. The most common variants are LH 2.2, which uses an [[Intel]] 8049 ([[Intel MCS-48|MCS-48]]) microcontroller, and usually a 4 [[kilobyte|kB]] programme memory, and LH 2.4, which uses a [[Siemens AG|Siemens]] 80535 microcontroller (a variant of Intel's 8051/[[Intel MCS-51|MCS-51]] architecture) and 32 kB programme memory based on the 27C256 chip. LH-Jetronic 2.4 has adaptive lambda control, and support for a variety of advanced features; including fuel enrichment based on [[exhaust gas]] temperature (ex. [[Volvo Redblock Engine|Volvo B204GT/B204FT engines]]). Some later (post-1995) versions contain hardware support for first generation diagnostics according to [[list of ISO standards#ISO 1000–ISO 9999|ISO 9141]] (a.k.a. [[on-board diagnostics#OBD-II|OBD-II]]) and immobiliser functions. {{citation needed|reason=Volvo 940 from 1995 and on was given as an example of this, but model year -95 has the older diagnosis box in the engine compartment, and while 1996–1998 do have an OBD-II style connector, they still use the older interface, not OBD-II.|date=May 2012}}