Question about Jeep Wrangler
Describe your 2003 Jeep Wrangle2007 Wrangler Unlimited - Died one day last week. Checked fuses, etc. Would crank but not start. Started and ran while spraying carb cleaner in intake, indicating PCM functional, spark functional, crank sensor functional. Did not locate schrader valve to check fuel pressure at rail. Replaced fuel pump. Same result, Crank no start. No codes. Now, when attempting to start, at times the starter will continue to run until key is turned off. This lead to a dead battery quickly so now attempts to start are performed with another vehicle connected to this one. Impossible for CKP sensor to be faulty and vehicle run on carb cleaner. . . ? Side note - Fuse 37 states it is for the Fuel Pump Relay. . . I was unable to locate a fuel pump relay. Fuse 25 is for the fuel pump. Both fuses are good, and fuse 25 has +12V with ignition on. Fuse 37 has -12V. Where might the fuel pump relay be if not in the fusebox? Alternate fusebox? Labeled as something different or using a relay that is used for something else as well?
The Start/Run relays produce a whining noise while the ignition is on, unsure if this is indicative of problems. Cannot recall hearing relay whine / hiss in all my years.r Problem
2.8L VM Motori RA 428 Diesel I4
Complete engine specs[show] 3.6L Pentastar V6
Complete engine specs[show] 3.8 L EGH V6
times the starter will continue to run until key is turned off.
that is starter relay bad or the puter running it gone nuts.
or bad starter
next time when starter latches up, pull the relay
if it kills the cranking its bad relay or puter
if not, bad starter. all in 1min work..
and a very very serious first ORDER fix first problem
runs on test fuel. but you failed to keep it running for the 2 -3 second JEEP RULE.
if you had here is the results. (logic) hard.
1: i can keep it running with spray need a video?
yes, means ASD is not dropping out
2: no? ASD is killing the engine on purpose. and scan tool told you.
cranks no start
"No codes." if really true , there is no fuel pressure.!
if not true, its done wrong. so scan correctly THIS time.
is the skim light glowing in the dash cluster, if yes, it will not start
by DESIGN. SKIM is the immobilizer and DOES!
you must scan WHILE l its failing, not after, WHILE.
HOW TO SCAN correctly on JEEPS, (no starts)
key on, see scanner working? now, it must, if not ask.
crank or 5 seconds, (1 potato , 2 potata, 3,4,5.
release key, ( 4 and 5 are overkill but why not?)
do not turn key off or say 2 minutes, get PCM time to REPORT.
scan (2008 or newer scan tools work, CAN-BUS certified)
the tool then tells you why the ASD RELAY dropped killing starting (by DESIGN)
try to know SKIM is and option, so.... me blind can see car
runs on test fuel longer that 3 seconds, by hand, means.
all is working mostly, the fuel pressure gauge needs a jeep hose kit to work so/....... the pump needs power to work,
now the acid tests
i have 2. acid tests lacking a real scan too;..
spark timing light connected up.
you crank and spark dies, AFTER 2-3 seconds into crank/start
cycle means ASD dropped.
connect meter to injector 12vdc power feed its a daisy chain
12vdc dies, at 3seconds of crank, or dies
at 3 seconds of running,
if true PCM did that , and is ASD drop doing that
running any jeep for 1 second on test fuel is a waste of time
it tells too little
learn that jeeps can drop a ASD at 100mph
any time it wants. and only scanning while it drops
tells you why, unless the SKIM lamp glows,
Posted on Mar 03, 2017
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Posted on Jan 02, 2017
starter relay and fuel pump relays should be inside the power distribution center near the battery generally they have a map printed into the inside of the cover. sounds like the starter relay failed during testing and pump relay failed causing the no-start. Strange noise could be a connection problem on underside connection of distribution center.Often, if you try to jump "through" a dead battery it will throw voltage off and systems will not function properly. Jumping from another vehicle can also cause damage to other vehicles charging system. charge your battery and if you need more power while testing, jump to another battery not in a vehicle before you begin, that will add time before system looses power. Also leave one terminal secure enough to be functional but loose enough so that if starter again remains on, you can quickly disconnect it.
Posted on Jun 19, 2009
Hey Tim take a look at this, will this help ?
No Engine Crank Or No Engine Start Due To Electronic Lockup Of The WCM / SKREEM
This bulletin involves the replacement of the Wireless Control Module (WCM), and if
equipped, the replacement of the Electric Steering Column Lock (ELV). The WCM is also
referred to as the Sentry Key Remote Entry Module (SKREEM).
The customer will experience a no engine crank AND a no engine start condition. Also, the
remote keyless entry (RKE) system will not operate. This condition may be due to an
electrostatic discharge (ESD) from the ignition key into the Wireless Control Module
(WCM), causing the WCM to electronically lockup. This condition may occur more
frequently in dry and/or cold weather conditions where a sufficient electrostatic charge is
more easily produced. This condition is corrected by the replacement of the WCM
1. With the condition present (i.e. the vehicle in the no crank / no start condition), connect
the StarSCAN® scan tool to the vehicle.
2. Turn the ignition switch to the “ON” position, and power up the StarSCAN®.
3. If the WCM is electronically locked up, the StarSCAN® will display the WCM as being
4. If the no crank / no start condition is present, and the WCM is “off bus”, then reset the
WCM by temporarily removing the IOD fuse (with the key out of the ignition switch),
wait for 10 seconds and then reinstall the IOD fuse.
5. With the IOD fuse reset having been performed, verify that the vehicle will now crank,
start, and run.
6. If the condition is temporarily corrected by performing the above steps, and if the part
number of the WCM is earlier than the part number of the WCM listed in the part
reference table in the Service Bulletin Parts Required Section below, then perform the
Posted on Jun 24, 2009
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