Bob S.
Top Post Dawg
BACKGROUND: 12 JSW w/ CJAA engine. 163K miles. Fix done, out of extended warranty. Acquired in a Cranks/Engine turns over, but no start/no run condition.
My initial VCDS scan produced only a couple error codes, the dreaded P2015 (& related codes) and the above related to the exhaust emissions. No other codes. The P2015 related codes were addressed, cleared and have not returned. DTCs: P2BA6 & P1A58 NOx exceedance & Regen required remained. In asking questions, it is understood that these codes will put it into limp mode, but not prevent starting.
The engine remains, a Crank/No start condition and appears to crank with compression.
CURRENT DIAGNOSTICS. The only DTCs are P2BA6 & P1A58 as above. So, I moved to the basics.
Intercooler piping checked. No water/ice blockage.
Replaced fuel filter. Dirty, but no visible contamination, rust or signs of HPFP failure. Filter check with magnet negative
When attempting to time the fuel system via VCDS (both methods), no in-tank or auxiliary fuel pump sounds were heard. I did hear relays under the dash clicking in sequence with the VCDS on/of status. But, no noise. Reopening the fuel filter found the same fuel level added at filter installation.
On line searches suggest that fuse box SC #47 (30A) is the fuse for the in-tank & aux. pump circuit. That fuse is visually good.
I do not have a good schematic for the fuel circuits or diagram of the system. (I have searched).
I am leaning towards heading down the Fuel diagnostics rabbit hole.
Solved & fixed. Pin testing identified a bad fuse in SC #27. 15A. Melted & blown. Cause for that remains to be identified. Cleaned terminals, new fuse/contacts cleaned & it started. I do understand that there is a circuit and probable pump(s) issue that remain to be identified & addressed. But, at least the variables are narrowed down. Thanks to those that responded & prevented me from heading down needless habit holes.
So, if some one with a 12 JSW CJAA manual is chasing fuel in tank & auxiliary pump & related circuit issues, the fuse for that circuit in my car is Box SC #27. 15A. (Surprise: Some information found on the internet is incorrect).
My initial VCDS scan produced only a couple error codes, the dreaded P2015 (& related codes) and the above related to the exhaust emissions. No other codes. The P2015 related codes were addressed, cleared and have not returned. DTCs: P2BA6 & P1A58 NOx exceedance & Regen required remained. In asking questions, it is understood that these codes will put it into limp mode, but not prevent starting.
The engine remains, a Crank/No start condition and appears to crank with compression.
CURRENT DIAGNOSTICS. The only DTCs are P2BA6 & P1A58 as above. So, I moved to the basics.
Intercooler piping checked. No water/ice blockage.
Replaced fuel filter. Dirty, but no visible contamination, rust or signs of HPFP failure. Filter check with magnet negative
When attempting to time the fuel system via VCDS (both methods), no in-tank or auxiliary fuel pump sounds were heard. I did hear relays under the dash clicking in sequence with the VCDS on/of status. But, no noise. Reopening the fuel filter found the same fuel level added at filter installation.
On line searches suggest that fuse box SC #47 (30A) is the fuse for the in-tank & aux. pump circuit. That fuse is visually good.
I do not have a good schematic for the fuel circuits or diagram of the system. (I have searched).
I am leaning towards heading down the Fuel diagnostics rabbit hole.
Solved & fixed. Pin testing identified a bad fuse in SC #27. 15A. Melted & blown. Cause for that remains to be identified. Cleaned terminals, new fuse/contacts cleaned & it started. I do understand that there is a circuit and probable pump(s) issue that remain to be identified & addressed. But, at least the variables are narrowed down. Thanks to those that responded & prevented me from heading down needless habit holes.
So, if some one with a 12 JSW CJAA manual is chasing fuel in tank & auxiliary pump & related circuit issues, the fuse for that circuit in my car is Box SC #27. 15A. (Surprise: Some information found on the internet is incorrect).
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